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quota: Move locking into clear_dquot_dirty()
[linux-2.6-block.git] / fs / quota / dquot.c
CommitLineData
1da177e4
LT		 1/*
2 * Implementation of the diskquota system for the LINUX operating system. QUOTA
3 * is implemented using the BSD system call interface as the means of
4 * communication with the user level. This file contains the generic routines
5 * called by the different filesystems on allocation of an inode or block.
6 * These routines take care of the administration needed to have a consistent
7 * diskquota tracking system. The ideas of both user and group quotas are based
8 * on the Melbourne quota system as used on BSD derived systems. The internal
9 * implementation is based on one of the several variants of the LINUX
10 * inode-subsystem with added complexity of the diskquota system.
11 *
1da177e4
LT		 12 * Author: Marco van Wieringen <mvw@planets.elm.net>
13 *
14 * Fixes: Dmitry Gorodchanin <pgmdsg@ibi.com>, 11 Feb 96
15 *
16 * Revised list management to avoid races
17 * -- Bill Hawes, <whawes@star.net>, 9/98
18 *
19 * Fixed races in dquot_transfer(), dqget() and dquot_alloc_...().
20 * As the consequence the locking was moved from dquot_decr_...(),
21 * dquot_incr_...() to calling functions.
22 * invalidate_dquots() now writes modified dquots.
23 * Serialized quota_off() and quota_on() for mount point.
24 * Fixed a few bugs in grow_dquots().
25 * Fixed deadlock in write_dquot() - we no longer account quotas on
26 * quota files
27 * remove_dquot_ref() moved to inode.c - it now traverses through inodes
28 * add_dquot_ref() restarts after blocking
29 * Added check for bogus uid and fixed check for group in quotactl.
30 * Jan Kara, <jack@suse.cz>, sponsored by SuSE CR, 10-11/99
31 *
32 * Used struct list_head instead of own list struct
33 * Invalidation of referenced dquots is no longer possible
34 * Improved free_dquots list management
35 * Quota and i_blocks are now updated in one place to avoid races
36 * Warnings are now delayed so we won't block in critical section
37 * Write updated not to require dquot lock
38 * Jan Kara, <jack@suse.cz>, 9/2000
39 *
40 * Added dynamic quota structure allocation
41 * Jan Kara <jack@suse.cz> 12/2000
42 *
43 * Rewritten quota interface. Implemented new quota format and
44 * formats registering.
45 * Jan Kara, <jack@suse.cz>, 2001,2002
46 *
47 * New SMP locking.
48 * Jan Kara, <jack@suse.cz>, 10/2002
49 *
50 * Added journalled quota support, fix lock inversion problems
51 * Jan Kara, <jack@suse.cz>, 2003,2004
52 *
53 * (C) Copyright 1994 - 1997 Marco van Wieringen
54 */
55
56#include <linux/errno.h>
57#include <linux/kernel.h>
58#include <linux/fs.h>
59#include <linux/mount.h>
60#include <linux/mm.h>
61#include <linux/time.h>
62#include <linux/types.h>
63#include <linux/string.h>
64#include <linux/fcntl.h>
65#include <linux/stat.h>
66#include <linux/tty.h>
67#include <linux/file.h>
68#include <linux/slab.h>
69#include <linux/sysctl.h>
1da177e4
LT		 70#include <linux/init.h>
71#include <linux/module.h>
72#include <linux/proc_fs.h>
73#include <linux/security.h>
40401530 74#include <linux/sched.h>
5b825c3a 75#include <linux/cred.h>
1da177e4
LT		 76#include <linux/kmod.h>
77#include <linux/namei.h>
16f7e0fe 78#include <linux/capability.h>
be586bab 79#include <linux/quotaops.h>
55fa6091 80#include "../internal.h" /* ugh */
1da177e4 81
f3da9310 82#include <linux/uaccess.h>
1da177e4 83
1da177e4 84/*
cc33412f 85 * There are three quota SMP locks. dq_list_lock protects all lists with quotas
dde95888 86 * and quota formats.
cc33412f
JK		 87 * dq_data_lock protects data from dq_dqb and also mem_dqinfo structures and
88 * also guards consistency of dquot->dq_dqb with inode->i_blocks, i_bytes.
1da177e4 89 * i_blocks and i_bytes updates itself are guarded by i_lock acquired directly
cc33412f
JK		 90 * in inode_add_bytes() and inode_sub_bytes(). dq_state_lock protects
91 * modifications of quota state (on quotaon and quotaoff) and readers who care
92 * about latest values take it as well.
1da177e4 93 *
cc33412f
JK		 94 * The spinlock ordering is hence: dq_data_lock > dq_list_lock > i_lock,
95 * dq_list_lock > dq_state_lock
1da177e4
LT		 96 *
97 * Note that some things (eg. sb pointer, type, id) doesn't change during
98 * the life of the dquot structure and so needn't to be protected by a lock
99 *
b9ba6f94
NY		 100 * Operation accessing dquots via inode pointers are protected by dquot_srcu.
101 * Operation of reading pointer needs srcu_read_lock(&dquot_srcu), and
102 * synchronize_srcu(&dquot_srcu) is called after clearing pointers from
103 * inode and before dropping dquot references to avoid use of dquots after
104 * they are freed. dq_data_lock is used to serialize the pointer setting and
105 * clearing operations.
26245c94
JK		 106 * Special care needs to be taken about S_NOQUOTA inode flag (marking that
107 * inode is a quota file). Functions adding pointers from inode to dquots have
b9ba6f94
NY		 108 * to check this flag under dq_data_lock and then (if S_NOQUOTA is not set) they
109 * have to do all pointer modifications before dropping dq_data_lock. This makes
26245c94
JK		 110 * sure they cannot race with quotaon which first sets S_NOQUOTA flag and
111 * then drops all pointers to dquots from an inode.
1da177e4 112 *
5e8cb9b6
JK		 113 * Each dquot has its dq_lock mutex. Dquot is locked when it is being read to
114 * memory (or space for it is being allocated) on the first dqget(), when it is
115 * being written out, and when it is being released on the last dqput(). The
116 * allocation and release operations are serialized by the dq_lock and by
117 * checking the use count in dquot_release().
1da177e4
LT		 118 *
119 * Lock ordering (including related VFS locks) is the following:
bc8230ee 120 * s_umount > i_mutex > journal_lock > dquot->dq_lock > dqio_sem
1da177e4
LT		 121 */
122
c516610c
JK		 123static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_list_lock);
124static __cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_state_lock);
125__cacheline_aligned_in_smp DEFINE_SPINLOCK(dq_data_lock);
08d0350c 126EXPORT_SYMBOL(dq_data_lock);
b9ba6f94 127DEFINE_STATIC_SRCU(dquot_srcu);
1da177e4 128
fb5ffb0e 129void __quota_error(struct super_block *sb, const char *func,
055adcbd 130 const char *fmt, ...)
fb5ffb0e 131{
fb5ffb0e 132 if (printk_ratelimit()) {
055adcbd
JP		 133 va_list args;
134 struct va_format vaf;
135
fb5ffb0e 136 va_start(args, fmt);
055adcbd
JP		 137
138 vaf.fmt = fmt;
139 vaf.va = &args;
140
141 printk(KERN_ERR "Quota error (device %s): %s: %pV\n",
142 sb->s_id, func, &vaf);
143
fb5ffb0e
JZ		 144 va_end(args);
145 }
146}
147EXPORT_SYMBOL(__quota_error);
148
da8d1ba2 149#if defined(CONFIG_QUOTA_DEBUG) || defined(CONFIG_PRINT_QUOTA_WARNING)
1da177e4 150static char *quotatypes[] = INITQFNAMES;
da8d1ba2 151#endif
1da177e4
LT		 152static struct quota_format_type *quota_formats; /* List of registered formats */
153static struct quota_module_name module_names[] = INIT_QUOTA_MODULE_NAMES;
154
155/* SLAB cache for dquot structures */
e18b890b 156static struct kmem_cache *dquot_cachep;
1da177e4
LT		 157
158int register_quota_format(struct quota_format_type *fmt)
159{
160 spin_lock(&dq_list_lock);
161 fmt->qf_next = quota_formats;
162 quota_formats = fmt;
163 spin_unlock(&dq_list_lock);
164 return 0;
165}
08d0350c 166EXPORT_SYMBOL(register_quota_format);
1da177e4
LT		 167
168void unregister_quota_format(struct quota_format_type *fmt)
169{
170 struct quota_format_type **actqf;
171
172 spin_lock(&dq_list_lock);
268157ba
JK		 173 for (actqf = &quota_formats; *actqf && *actqf != fmt;
174 actqf = &(*actqf)->qf_next)
175 ;
1da177e4
LT		 176 if (*actqf)
177 *actqf = (*actqf)->qf_next;
178 spin_unlock(&dq_list_lock);
179}
08d0350c 180EXPORT_SYMBOL(unregister_quota_format);
1da177e4
LT		 181
182static struct quota_format_type *find_quota_format(int id)
183{
184 struct quota_format_type *actqf;
185
186 spin_lock(&dq_list_lock);
268157ba
JK		 187 for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id;
188 actqf = actqf->qf_next)
189 ;
1da177e4
LT		 190 if (!actqf || !try_module_get(actqf->qf_owner)) {
191 int qm;
192
193 spin_unlock(&dq_list_lock);
194
268157ba
JK		 195 for (qm = 0; module_names[qm].qm_fmt_id &&
196 module_names[qm].qm_fmt_id != id; qm++)
197 ;
198 if (!module_names[qm].qm_fmt_id ||
199 request_module(module_names[qm].qm_mod_name))
1da177e4
LT		 200 return NULL;
201
202 spin_lock(&dq_list_lock);
268157ba
JK		 203 for (actqf = quota_formats; actqf && actqf->qf_fmt_id != id;
204 actqf = actqf->qf_next)
205 ;
1da177e4
LT		 206 if (actqf && !try_module_get(actqf->qf_owner))
207 actqf = NULL;
208 }
209 spin_unlock(&dq_list_lock);
210 return actqf;
211}
212
213static void put_quota_format(struct quota_format_type *fmt)
214{
215 module_put(fmt->qf_owner);
216}
217
218/*
219 * Dquot List Management:
220 * The quota code uses three lists for dquot management: the inuse_list,
221 * free_dquots, and dquot_hash[] array. A single dquot structure may be
222 * on all three lists, depending on its current state.
223 *
224 * All dquots are placed to the end of inuse_list when first created, and this
225 * list is used for invalidate operation, which must look at every dquot.
226 *
227 * Unused dquots (dq_count == 0) are added to the free_dquots list when freed,
228 * and this list is searched whenever we need an available dquot. Dquots are
229 * removed from the list as soon as they are used again, and
230 * dqstats.free_dquots gives the number of dquots on the list. When
231 * dquot is invalidated it's completely released from memory.
232 *
233 * Dquots with a specific identity (device, type and id) are placed on
234 * one of the dquot_hash[] hash chains. The provides an efficient search
235 * mechanism to locate a specific dquot.
236 */
237
238static LIST_HEAD(inuse_list);
239static LIST_HEAD(free_dquots);
240static unsigned int dq_hash_bits, dq_hash_mask;
241static struct hlist_head *dquot_hash;
242
243struct dqstats dqstats;
08d0350c 244EXPORT_SYMBOL(dqstats);
1da177e4 245
0a5a9c72 246static qsize_t inode_get_rsv_space(struct inode *inode);
6184fc0b 247static int __dquot_initialize(struct inode *inode, int type);
0a5a9c72 248
1da177e4 249static inline unsigned int
1a06d420 250hashfn(const struct super_block *sb, struct kqid qid)
1da177e4 251{
1a06d420
EB		 252 unsigned int id = from_kqid(&init_user_ns, qid);
253 int type = qid.type;
1da177e4
LT		 254 unsigned long tmp;
255
256 tmp = (((unsigned long)sb>>L1_CACHE_SHIFT) ^ id) * (MAXQUOTAS - type);
257 return (tmp + (tmp >> dq_hash_bits)) & dq_hash_mask;
258}
259
260/*
261 * Following list functions expect dq_list_lock to be held
262 */
263static inline void insert_dquot_hash(struct dquot *dquot)
264{
268157ba 265 struct hlist_head *head;
1a06d420 266 head = dquot_hash + hashfn(dquot->dq_sb, dquot->dq_id);
1da177e4
LT		 267 hlist_add_head(&dquot->dq_hash, head);
268}
269
270static inline void remove_dquot_hash(struct dquot *dquot)
271{
272 hlist_del_init(&dquot->dq_hash);
273}
274
7a2435d8 275static struct dquot *find_dquot(unsigned int hashent, struct super_block *sb,
1a06d420 276 struct kqid qid)
1da177e4
LT		 277{
278 struct hlist_node *node;
279 struct dquot *dquot;
280
281 hlist_for_each (node, dquot_hash+hashent) {
282 dquot = hlist_entry(node, struct dquot, dq_hash);
4c376dca 283 if (dquot->dq_sb == sb && qid_eq(dquot->dq_id, qid))
1da177e4
LT		 284 return dquot;
285 }
dd6f3c6d 286 return NULL;
1da177e4
LT		 287}
288
289/* Add a dquot to the tail of the free list */
290static inline void put_dquot_last(struct dquot *dquot)
291{
8e13059a 292 list_add_tail(&dquot->dq_free, &free_dquots);
dde95888 293 dqstats_inc(DQST_FREE_DQUOTS);
1da177e4
LT		 294}
295
296static inline void remove_free_dquot(struct dquot *dquot)
297{
298 if (list_empty(&dquot->dq_free))
299 return;
300 list_del_init(&dquot->dq_free);
dde95888 301 dqstats_dec(DQST_FREE_DQUOTS);
1da177e4
LT		 302}
303
304static inline void put_inuse(struct dquot *dquot)
305{
306 /* We add to the back of inuse list so we don't have to restart
307 * when traversing this list and we block */
8e13059a 308 list_add_tail(&dquot->dq_inuse, &inuse_list);
dde95888 309 dqstats_inc(DQST_ALLOC_DQUOTS);
1da177e4
LT		 310}
311
312static inline void remove_inuse(struct dquot *dquot)
313{
dde95888 314 dqstats_dec(DQST_ALLOC_DQUOTS);
1da177e4
LT		 315 list_del(&dquot->dq_inuse);
316}
317/*
318 * End of list functions needing dq_list_lock
319 */
320
321static void wait_on_dquot(struct dquot *dquot)
322{
d3be915f
IM		 323 mutex_lock(&dquot->dq_lock);
324 mutex_unlock(&dquot->dq_lock);
1da177e4
LT		 325}
326
03f6e92b
JK		 327static inline int dquot_dirty(struct dquot *dquot)
328{
329 return test_bit(DQ_MOD_B, &dquot->dq_flags);
330}
331
332static inline int mark_dquot_dirty(struct dquot *dquot)
333{
334 return dquot->dq_sb->dq_op->mark_dirty(dquot);
335}
1da177e4 336
eabf290d 337/* Mark dquot dirty in atomic manner, and return it's old dirty flag state */
1da177e4
LT		 338int dquot_mark_dquot_dirty(struct dquot *dquot)
339{
eabf290d
DM		 340 int ret = 1;
341
4580b30e
JK		 342 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags))
343 return 0;
344
eabf290d
DM		 345 /* If quota is dirty already, we don't have to acquire dq_list_lock */
346 if (test_bit(DQ_MOD_B, &dquot->dq_flags))
347 return 1;
348
1da177e4 349 spin_lock(&dq_list_lock);
eabf290d 350 if (!test_and_set_bit(DQ_MOD_B, &dquot->dq_flags)) {
1da177e4 351 list_add(&dquot->dq_dirty, &sb_dqopt(dquot->dq_sb)->
4c376dca 352 info[dquot->dq_id.type].dqi_dirty_list);
eabf290d
DM		 353 ret = 0;
354 }
1da177e4 355 spin_unlock(&dq_list_lock);
eabf290d 356 return ret;
1da177e4 357}
08d0350c 358EXPORT_SYMBOL(dquot_mark_dquot_dirty);
1da177e4 359
dc52dd3a
DM		 360/* Dirtify all the dquots - this can block when journalling */
361static inline int mark_all_dquot_dirty(struct dquot * const *dquot)
362{
363 int ret, err, cnt;
364
365 ret = err = 0;
366 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
367 if (dquot[cnt])
368 /* Even in case of error we have to continue */
369 ret = mark_dquot_dirty(dquot[cnt]);
370 if (!err)
371 err = ret;
372 }
373 return err;
374}
375
376static inline void dqput_all(struct dquot **dquot)
377{
378 unsigned int cnt;
379
380 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
381 dqput(dquot[cnt]);
382}
383
1da177e4
LT		 384static inline int clear_dquot_dirty(struct dquot *dquot)
385{
1e0b7cb0
JK		 386 spin_lock(&dq_list_lock);
387 if (!test_and_clear_bit(DQ_MOD_B, &dquot->dq_flags)) {
388 spin_unlock(&dq_list_lock);
1da177e4 389 return 0;
1e0b7cb0 390 }
1da177e4 391 list_del_init(&dquot->dq_dirty);
1e0b7cb0 392 spin_unlock(&dq_list_lock);
1da177e4
LT		 393 return 1;
394}
395
396void mark_info_dirty(struct super_block *sb, int type)
397{
15512377
JK		 398 spin_lock(&dq_data_lock);
399 sb_dqopt(sb)->info[type].dqi_flags |= DQF_INFO_DIRTY;
400 spin_unlock(&dq_data_lock);
1da177e4
LT		 401}
402EXPORT_SYMBOL(mark_info_dirty);
403
404/*
405 * Read dquot from disk and alloc space for it
406 */
407
408int dquot_acquire(struct dquot *dquot)
409{
410 int ret = 0, ret2 = 0;
411 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
412
d3be915f 413 mutex_lock(&dquot->dq_lock);
e342e38d 414 if (!test_bit(DQ_READ_B, &dquot->dq_flags))
4c376dca 415 ret = dqopt->ops[dquot->dq_id.type]->read_dqblk(dquot);
1da177e4
LT		 416 if (ret < 0)
417 goto out_iolock;
044c9b67
JK		 418 /* Make sure flags update is visible after dquot has been filled */
419 smp_mb__before_atomic();
1da177e4
LT		 420 set_bit(DQ_READ_B, &dquot->dq_flags);
421 /* Instantiate dquot if needed */
422 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags) && !dquot->dq_off) {
4c376dca 423 ret = dqopt->ops[dquot->dq_id.type]->commit_dqblk(dquot);
1da177e4 424 /* Write the info if needed */
4c376dca
EB		 425 if (info_dirty(&dqopt->info[dquot->dq_id.type])) {
426 ret2 = dqopt->ops[dquot->dq_id.type]->write_file_info(
427 dquot->dq_sb, dquot->dq_id.type);
268157ba 428 }
1da177e4
LT		 429 if (ret < 0)
430 goto out_iolock;
431 if (ret2 < 0) {
432 ret = ret2;
433 goto out_iolock;
434 }
435 }
044c9b67
JK		 436 /*
437 * Make sure flags update is visible after on-disk struct has been
438 * allocated. Paired with smp_rmb() in dqget().
439 */
440 smp_mb__before_atomic();
1da177e4
LT		 441 set_bit(DQ_ACTIVE_B, &dquot->dq_flags);
442out_iolock:
d3be915f 443 mutex_unlock(&dquot->dq_lock);
1da177e4
LT		 444 return ret;
445}
08d0350c 446EXPORT_SYMBOL(dquot_acquire);
1da177e4
LT		 447
448/*
449 * Write dquot to disk
450 */
451int dquot_commit(struct dquot *dquot)
452{
b03f2456 453 int ret = 0;
1da177e4
LT		 454 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
455
5e8cb9b6 456 mutex_lock(&dquot->dq_lock);
1e0b7cb0 457 if (!clear_dquot_dirty(dquot))
5e8cb9b6 458 goto out_lock;
1da177e4
LT		 459 /* Inactive dquot can be only if there was error during read/init
460 * => we have better not writing it */
8fc32c2b 461 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags))
4c376dca 462 ret = dqopt->ops[dquot->dq_id.type]->commit_dqblk(dquot);
8fc32c2b 463 else
b03f2456 464 ret = -EIO;
5e8cb9b6
JK		 465out_lock:
466 mutex_unlock(&dquot->dq_lock);
1da177e4
LT		 467 return ret;
468}
08d0350c 469EXPORT_SYMBOL(dquot_commit);
1da177e4
LT		 470
471/*
472 * Release dquot
473 */
474int dquot_release(struct dquot *dquot)
475{
476 int ret = 0, ret2 = 0;
477 struct quota_info *dqopt = sb_dqopt(dquot->dq_sb);
478
d3be915f 479 mutex_lock(&dquot->dq_lock);
1da177e4
LT		 480 /* Check whether we are not racing with some other dqget() */
481 if (atomic_read(&dquot->dq_count) > 1)
482 goto out_dqlock;
4c376dca
EB		 483 if (dqopt->ops[dquot->dq_id.type]->release_dqblk) {
484 ret = dqopt->ops[dquot->dq_id.type]->release_dqblk(dquot);
1da177e4 485 /* Write the info */
4c376dca
EB		 486 if (info_dirty(&dqopt->info[dquot->dq_id.type])) {
487 ret2 = dqopt->ops[dquot->dq_id.type]->write_file_info(
488 dquot->dq_sb, dquot->dq_id.type);
268157ba 489 }
1da177e4
LT		 490 if (ret >= 0)
491 ret = ret2;
492 }
493 clear_bit(DQ_ACTIVE_B, &dquot->dq_flags);
1da177e4 494out_dqlock:
d3be915f 495 mutex_unlock(&dquot->dq_lock);
1da177e4
LT		 496 return ret;
497}
08d0350c 498EXPORT_SYMBOL(dquot_release);
1da177e4 499
7d9056ba 500void dquot_destroy(struct dquot *dquot)
74f783af
JK		 501{
502 kmem_cache_free(dquot_cachep, dquot);
503}
7d9056ba 504EXPORT_SYMBOL(dquot_destroy);
74f783af
JK		 505
506static inline void do_destroy_dquot(struct dquot *dquot)
507{
508 dquot->dq_sb->dq_op->destroy_dquot(dquot);
509}
510
1da177e4
LT		 511/* Invalidate all dquots on the list. Note that this function is called after
512 * quota is disabled and pointers from inodes removed so there cannot be new
6362e4d4
JK		 513 * quota users. There can still be some users of quotas due to inodes being
514 * just deleted or pruned by prune_icache() (those are not attached to any
cc33412f 515 * list) or parallel quotactl call. We have to wait for such users.
6362e4d4 516 */
1da177e4
LT		 517static void invalidate_dquots(struct super_block *sb, int type)
518{
c33ed271 519 struct dquot *dquot, *tmp;
1da177e4 520
6362e4d4 521restart:
1da177e4 522 spin_lock(&dq_list_lock);
c33ed271 523 list_for_each_entry_safe(dquot, tmp, &inuse_list, dq_inuse) {
1da177e4
LT		 524 if (dquot->dq_sb != sb)
525 continue;
4c376dca 526 if (dquot->dq_id.type != type)
1da177e4 527 continue;
6362e4d4
JK		 528 /* Wait for dquot users */
529 if (atomic_read(&dquot->dq_count)) {
530 DEFINE_WAIT(wait);
531
9f985cb6 532 dqgrab(dquot);
6362e4d4
JK		 533 prepare_to_wait(&dquot->dq_wait_unused, &wait,
534 TASK_UNINTERRUPTIBLE);
535 spin_unlock(&dq_list_lock);
536 /* Once dqput() wakes us up, we know it's time to free
537 * the dquot.
538 * IMPORTANT: we rely on the fact that there is always
539 * at most one process waiting for dquot to free.
540 * Otherwise dq_count would be > 1 and we would never
541 * wake up.
542 */
543 if (atomic_read(&dquot->dq_count) > 1)
544 schedule();
545 finish_wait(&dquot->dq_wait_unused, &wait);
546 dqput(dquot);
547 /* At this moment dquot() need not exist (it could be
548 * reclaimed by prune_dqcache(). Hence we must
549 * restart. */
550 goto restart;
551 }
552 /*
553 * Quota now has no users and it has been written on last
554 * dqput()
555 */
1da177e4
LT		 556 remove_dquot_hash(dquot);
557 remove_free_dquot(dquot);
558 remove_inuse(dquot);
74f783af 559 do_destroy_dquot(dquot);
1da177e4
LT		 560 }
561 spin_unlock(&dq_list_lock);
562}
563
12c77527
JK		 564/* Call callback for every active dquot on given filesystem */
565int dquot_scan_active(struct super_block *sb,
566 int (*fn)(struct dquot *dquot, unsigned long priv),
567 unsigned long priv)
568{
569 struct dquot *dquot, *old_dquot = NULL;
570 int ret = 0;
571
ee1ac541
JK		 572 WARN_ON_ONCE(!rwsem_is_locked(&sb->s_umount));
573
12c77527
JK		 574 spin_lock(&dq_list_lock);
575 list_for_each_entry(dquot, &inuse_list, dq_inuse) {
576 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags))
577 continue;
578 if (dquot->dq_sb != sb)
579 continue;
580 /* Now we have active dquot so we can just increase use count */
581 atomic_inc(&dquot->dq_count);
12c77527 582 spin_unlock(&dq_list_lock);
dde95888 583 dqstats_inc(DQST_LOOKUPS);
12c77527
JK		 584 dqput(old_dquot);
585 old_dquot = dquot;
1362f4ea
JK		 586 /*
587 * ->release_dquot() can be racing with us. Our reference
588 * protects us from new calls to it so just wait for any
589 * outstanding call and recheck the DQ_ACTIVE_B after that.
590 */
591 wait_on_dquot(dquot);
592 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
593 ret = fn(dquot, priv);
594 if (ret < 0)
595 goto out;
596 }
12c77527
JK		 597 spin_lock(&dq_list_lock);
598 /* We are safe to continue now because our dquot could not
599 * be moved out of the inuse list while we hold the reference */
600 }
601 spin_unlock(&dq_list_lock);
602out:
603 dqput(old_dquot);
12c77527
JK		 604 return ret;
605}
08d0350c 606EXPORT_SYMBOL(dquot_scan_active);
12c77527 607
ceed1723
JK		 608/* Write all dquot structures to quota files */
609int dquot_writeback_dquots(struct super_block *sb, int type)
1da177e4
LT		 610{
611 struct list_head *dirty;
612 struct dquot *dquot;
613 struct quota_info *dqopt = sb_dqopt(sb);
614 int cnt;
ceed1723 615 int err, ret = 0;
1da177e4 616
9d1ccbe7
JK		 617 WARN_ON_ONCE(!rwsem_is_locked(&sb->s_umount));
618
1da177e4
LT		 619 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
620 if (type != -1 && cnt != type)
621 continue;
f55abc0f 622 if (!sb_has_quota_active(sb, cnt))
1da177e4
LT		 623 continue;
624 spin_lock(&dq_list_lock);
625 dirty = &dqopt->info[cnt].dqi_dirty_list;
626 while (!list_empty(dirty)) {
268157ba
JK		 627 dquot = list_first_entry(dirty, struct dquot,
628 dq_dirty);
4580b30e
JK		 629
630 WARN_ON(!test_bit(DQ_ACTIVE_B, &dquot->dq_flags));
631
1da177e4
LT		 632 /* Now we have active dquot from which someone is
633 * holding reference so we can safely just increase
634 * use count */
9f985cb6 635 dqgrab(dquot);
1da177e4 636 spin_unlock(&dq_list_lock);
dde95888 637 dqstats_inc(DQST_LOOKUPS);
ceed1723
JK		 638 err = sb->dq_op->write_dquot(dquot);
639 if (!ret && err)
474d2605 640 ret = err;
1da177e4
LT		 641 dqput(dquot);
642 spin_lock(&dq_list_lock);
643 }
644 spin_unlock(&dq_list_lock);
645 }
646
647 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
f55abc0f
JK		 648 if ((cnt == type || type == -1) && sb_has_quota_active(sb, cnt)
649 && info_dirty(&dqopt->info[cnt]))
1da177e4 650 sb->dq_op->write_info(sb, cnt);
dde95888 651 dqstats_inc(DQST_SYNCS);
1da177e4 652
ceed1723
JK		 653 return ret;
654}
655EXPORT_SYMBOL(dquot_writeback_dquots);
656
657/* Write all dquot structures to disk and make them visible from userspace */
658int dquot_quota_sync(struct super_block *sb, int type)
659{
660 struct quota_info *dqopt = sb_dqopt(sb);
661 int cnt;
662 int ret;
663
664 ret = dquot_writeback_dquots(sb, type);
665 if (ret)
666 return ret;
667 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE)
5fb324ad
CH		 668 return 0;
669
670 /* This is not very clever (and fast) but currently I don't know about
671 * any other simple way of getting quota data to disk and we must get
672 * them there for userspace to be visible... */
673 if (sb->s_op->sync_fs)
674 sb->s_op->sync_fs(sb, 1);
675 sync_blockdev(sb->s_bdev);
676
677 /*
678 * Now when everything is written we can discard the pagecache so
679 * that userspace sees the changes.
680 */
5fb324ad
CH		 681 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
682 if (type != -1 && cnt != type)
683 continue;
684 if (!sb_has_quota_active(sb, cnt))
685 continue;
5955102c 686 inode_lock(dqopt->files[cnt]);
f9ef1784 687 truncate_inode_pages(&dqopt->files[cnt]->i_data, 0);
5955102c 688 inode_unlock(dqopt->files[cnt]);
5fb324ad 689 }
5fb324ad 690
1da177e4
LT		 691 return 0;
692}
287a8095 693EXPORT_SYMBOL(dquot_quota_sync);
1da177e4 694
1ab6c499
DC		 695static unsigned long
696dqcache_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
1da177e4
LT		 697{
698 struct list_head *head;
699 struct dquot *dquot;
1ab6c499 700 unsigned long freed = 0;
1da177e4 701
d68aab6b 702 spin_lock(&dq_list_lock);
1da177e4 703 head = free_dquots.prev;
1ab6c499 704 while (head != &free_dquots && sc->nr_to_scan) {
1da177e4
LT		 705 dquot = list_entry(head, struct dquot, dq_free);
706 remove_dquot_hash(dquot);
707 remove_free_dquot(dquot);
708 remove_inuse(dquot);
74f783af 709 do_destroy_dquot(dquot);
1ab6c499
DC		 710 sc->nr_to_scan--;
711 freed++;
1da177e4
LT		 712 head = free_dquots.prev;
713 }
d68aab6b 714 spin_unlock(&dq_list_lock);
1ab6c499 715 return freed;
1da177e4
LT		 716}
717
1ab6c499
DC		 718static unsigned long
719dqcache_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
1da177e4 720{
55f841ce
GC		 721 return vfs_pressure_ratio(
722 percpu_counter_read_positive(&dqstats.counter[DQST_FREE_DQUOTS]));
1da177e4
LT		 723}
724
8e1f936b 725static struct shrinker dqcache_shrinker = {
1ab6c499
DC		 726 .count_objects = dqcache_shrink_count,
727 .scan_objects = dqcache_shrink_scan,
8e1f936b
RR		 728 .seeks = DEFAULT_SEEKS,
729};
730
1da177e4
LT		 731/*
732 * Put reference to dquot
1da177e4 733 */
3d9ea253 734void dqput(struct dquot *dquot)
1da177e4 735{
b48d3805
JK		 736 int ret;
737
1da177e4
LT		 738 if (!dquot)
739 return;
62af9b52 740#ifdef CONFIG_QUOTA_DEBUG
1da177e4 741 if (!atomic_read(&dquot->dq_count)) {
fb5ffb0e 742 quota_error(dquot->dq_sb, "trying to free free dquot of %s %d",
4c376dca
EB		 743 quotatypes[dquot->dq_id.type],
744 from_kqid(&init_user_ns, dquot->dq_id));
1da177e4
LT		 745 BUG();
746 }
747#endif
dde95888 748 dqstats_inc(DQST_DROPS);
1da177e4
LT		 749we_slept:
750 spin_lock(&dq_list_lock);
751 if (atomic_read(&dquot->dq_count) > 1) {
752 /* We have more than one user... nothing to do */
753 atomic_dec(&dquot->dq_count);
6362e4d4 754 /* Releasing dquot during quotaoff phase? */
4c376dca 755 if (!sb_has_quota_active(dquot->dq_sb, dquot->dq_id.type) &&
6362e4d4
JK		 756 atomic_read(&dquot->dq_count) == 1)
757 wake_up(&dquot->dq_wait_unused);
1da177e4
LT		 758 spin_unlock(&dq_list_lock);
759 return;
760 }
761 /* Need to release dquot? */
4580b30e 762 if (dquot_dirty(dquot)) {
1da177e4
LT		 763 spin_unlock(&dq_list_lock);
764 /* Commit dquot before releasing */
b48d3805
JK		 765 ret = dquot->dq_sb->dq_op->write_dquot(dquot);
766 if (ret < 0) {
fb5ffb0e
JZ		 767 quota_error(dquot->dq_sb, "Can't write quota structure"
768 " (error %d). Quota may get out of sync!",
769 ret);
b48d3805
JK		 770 /*
771 * We clear dirty bit anyway, so that we avoid
772 * infinite loop here
773 */
b48d3805 774 clear_dquot_dirty(dquot);
b48d3805 775 }
1da177e4
LT		 776 goto we_slept;
777 }
1da177e4
LT		 778 if (test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
779 spin_unlock(&dq_list_lock);
780 dquot->dq_sb->dq_op->release_dquot(dquot);
781 goto we_slept;
782 }
783 atomic_dec(&dquot->dq_count);
62af9b52 784#ifdef CONFIG_QUOTA_DEBUG
1da177e4 785 /* sanity check */
8abf6a47 786 BUG_ON(!list_empty(&dquot->dq_free));
1da177e4
LT		 787#endif
788 put_dquot_last(dquot);
789 spin_unlock(&dq_list_lock);
790}
08d0350c 791EXPORT_SYMBOL(dqput);
1da177e4 792
7d9056ba 793struct dquot *dquot_alloc(struct super_block *sb, int type)
74f783af
JK		 794{
795 return kmem_cache_zalloc(dquot_cachep, GFP_NOFS);
796}
7d9056ba 797EXPORT_SYMBOL(dquot_alloc);
74f783af 798
1da177e4
LT		 799static struct dquot *get_empty_dquot(struct super_block *sb, int type)
800{
801 struct dquot *dquot;
802
74f783af 803 dquot = sb->dq_op->alloc_dquot(sb, type);
1da177e4 804 if(!dquot)
dd6f3c6d 805 return NULL;
1da177e4 806
d3be915f 807 mutex_init(&dquot->dq_lock);
1da177e4
LT		 808 INIT_LIST_HEAD(&dquot->dq_free);
809 INIT_LIST_HEAD(&dquot->dq_inuse);
810 INIT_HLIST_NODE(&dquot->dq_hash);
811 INIT_LIST_HEAD(&dquot->dq_dirty);
6362e4d4 812 init_waitqueue_head(&dquot->dq_wait_unused);
1da177e4 813 dquot->dq_sb = sb;
1a06d420 814 dquot->dq_id = make_kqid_invalid(type);
1da177e4
LT		 815 atomic_set(&dquot->dq_count, 1);
816
817 return dquot;
818}
819
820/*
821 * Get reference to dquot
cc33412f
JK		 822 *
823 * Locking is slightly tricky here. We are guarded from parallel quotaoff()
824 * destroying our dquot by:
825 * a) checking for quota flags under dq_list_lock and
826 * b) getting a reference to dquot before we release dq_list_lock
1da177e4 827 */
aca645a6 828struct dquot *dqget(struct super_block *sb, struct kqid qid)
1da177e4 829{
1a06d420 830 unsigned int hashent = hashfn(sb, qid);
6184fc0b 831 struct dquot *dquot, *empty = NULL;
1da177e4 832
d49d3762
EB		 833 if (!qid_has_mapping(sb->s_user_ns, qid))
834 return ERR_PTR(-EINVAL);
835
1a06d420 836 if (!sb_has_quota_active(sb, qid.type))
6184fc0b 837 return ERR_PTR(-ESRCH);
1da177e4
LT		 838we_slept:
839 spin_lock(&dq_list_lock);
cc33412f 840 spin_lock(&dq_state_lock);
1a06d420 841 if (!sb_has_quota_active(sb, qid.type)) {
cc33412f
JK		 842 spin_unlock(&dq_state_lock);
843 spin_unlock(&dq_list_lock);
6184fc0b 844 dquot = ERR_PTR(-ESRCH);
cc33412f
JK		 845 goto out;
846 }
847 spin_unlock(&dq_state_lock);
848
1a06d420 849 dquot = find_dquot(hashent, sb, qid);
dd6f3c6d
JK		 850 if (!dquot) {
851 if (!empty) {
1da177e4 852 spin_unlock(&dq_list_lock);
1a06d420 853 empty = get_empty_dquot(sb, qid.type);
dd6f3c6d 854 if (!empty)
1da177e4
LT		 855 schedule(); /* Try to wait for a moment... */
856 goto we_slept;
857 }
858 dquot = empty;
dd6f3c6d 859 empty = NULL;
4c376dca 860 dquot->dq_id = qid;
1da177e4
LT		 861 /* all dquots go on the inuse_list */
862 put_inuse(dquot);
863 /* hash it first so it can be found */
864 insert_dquot_hash(dquot);
1da177e4 865 spin_unlock(&dq_list_lock);
dde95888 866 dqstats_inc(DQST_LOOKUPS);
1da177e4
LT		 867 } else {
868 if (!atomic_read(&dquot->dq_count))
869 remove_free_dquot(dquot);
870 atomic_inc(&dquot->dq_count);
1da177e4 871 spin_unlock(&dq_list_lock);
dde95888
DM		 872 dqstats_inc(DQST_CACHE_HITS);
873 dqstats_inc(DQST_LOOKUPS);
1da177e4 874 }
268157ba
JK		 875 /* Wait for dq_lock - after this we know that either dquot_release() is
876 * already finished or it will be canceled due to dq_count > 1 test */
1da177e4 877 wait_on_dquot(dquot);
268157ba 878 /* Read the dquot / allocate space in quota file */
6184fc0b
JK		 879 if (!test_bit(DQ_ACTIVE_B, &dquot->dq_flags)) {
880 int err;
881
882 err = sb->dq_op->acquire_dquot(dquot);
883 if (err < 0) {
884 dqput(dquot);
885 dquot = ERR_PTR(err);
886 goto out;
887 }
1da177e4 888 }
044c9b67
JK		 889 /*
890 * Make sure following reads see filled structure - paired with
891 * smp_mb__before_atomic() in dquot_acquire().
892 */
893 smp_rmb();
62af9b52 894#ifdef CONFIG_QUOTA_DEBUG
8abf6a47 895 BUG_ON(!dquot->dq_sb); /* Has somebody invalidated entry under us? */
1da177e4 896#endif
cc33412f
JK		 897out:
898 if (empty)
899 do_destroy_dquot(empty);
1da177e4
LT		 900
901 return dquot;
902}
08d0350c 903EXPORT_SYMBOL(dqget);
1da177e4 904
2d0fa467
JK		 905static inline struct dquot **i_dquot(struct inode *inode)
906{
2d0fa467
JK		 907 return inode->i_sb->s_op->get_dquots(inode);
908}
909
1da177e4
LT		 910static int dqinit_needed(struct inode *inode, int type)
911{
5bcd3b6f 912 struct dquot * const *dquots;
1da177e4
LT		 913 int cnt;
914
915 if (IS_NOQUOTA(inode))
916 return 0;
5bcd3b6f
KK		 917
918 dquots = i_dquot(inode);
1da177e4 919 if (type != -1)
5bcd3b6f 920 return !dquots[type];
1da177e4 921 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
5bcd3b6f 922 if (!dquots[cnt])
1da177e4
LT		 923 return 1;
924 return 0;
925}
926
c3b00446 927/* This routine is guarded by s_umount semaphore */
1da177e4
LT		 928static void add_dquot_ref(struct super_block *sb, int type)
929{
941d2380 930 struct inode *inode, *old_inode = NULL;
62af9b52 931#ifdef CONFIG_QUOTA_DEBUG
0a5a9c72 932 int reserved = 0;
4c5e6c0e 933#endif
1da177e4 934
74278da9 935 spin_lock(&sb->s_inode_list_lock);
d003fb70 936 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
250df6ed
DC		 937 spin_lock(&inode->i_lock);
938 if ((inode->i_state & (I_FREEING|I_WILL_FREE|I_NEW)) ||
939 !atomic_read(&inode->i_writecount) ||
940 !dqinit_needed(inode, type)) {
941 spin_unlock(&inode->i_lock);
aabb8fdb 942 continue;
250df6ed 943 }
d003fb70 944 __iget(inode);
250df6ed 945 spin_unlock(&inode->i_lock);
74278da9 946 spin_unlock(&sb->s_inode_list_lock);
d003fb70 947
d7e97117
JK		 948#ifdef CONFIG_QUOTA_DEBUG
949 if (unlikely(inode_get_rsv_space(inode) > 0))
950 reserved = 1;
951#endif
941d2380 952 iput(old_inode);
871a2931 953 __dquot_initialize(inode, type);
55fa6091
DC		 954
955 /*
956 * We hold a reference to 'inode' so it couldn't have been
957 * removed from s_inodes list while we dropped the
74278da9 958 * s_inode_list_lock. We cannot iput the inode now as we can be
55fa6091 959 * holding the last reference and we cannot iput it under
74278da9 960 * s_inode_list_lock. So we keep the reference and iput it
55fa6091
DC		 961 * later.
962 */
941d2380 963 old_inode = inode;
74278da9 964 spin_lock(&sb->s_inode_list_lock);
1da177e4 965 }
74278da9 966 spin_unlock(&sb->s_inode_list_lock);
941d2380 967 iput(old_inode);
0a5a9c72 968
62af9b52 969#ifdef CONFIG_QUOTA_DEBUG
0a5a9c72 970 if (reserved) {
fb5ffb0e
JZ		 971 quota_error(sb, "Writes happened before quota was turned on "
972 "thus quota information is probably inconsistent. "
973 "Please run quotacheck(8)");
0a5a9c72 974 }
4c5e6c0e 975#endif
1da177e4
LT		 976}
977
268157ba
JK		 978/*
979 * Remove references to dquots from inode and add dquot to list for freeing
25985edc 980 * if we have the last reference to dquot
268157ba 981 */
9eb6463f
NY		 982static void remove_inode_dquot_ref(struct inode *inode, int type,
983 struct list_head *tofree_head)
1da177e4 984{
5bcd3b6f
KK		 985 struct dquot **dquots = i_dquot(inode);
986 struct dquot *dquot = dquots[type];
1da177e4 987
9eb6463f
NY		 988 if (!dquot)
989 return;
990
5bcd3b6f 991 dquots[type] = NULL;
9eb6463f
NY		 992 if (list_empty(&dquot->dq_free)) {
993 /*
994 * The inode still has reference to dquot so it can't be in the
995 * free list
996 */
997 spin_lock(&dq_list_lock);
998 list_add(&dquot->dq_free, tofree_head);
999 spin_unlock(&dq_list_lock);
1000 } else {
1001 /*
1002 * Dquot is already in a list to put so we won't drop the last
1003 * reference here.
1004 */
1005 dqput(dquot);
1da177e4 1006 }
1da177e4
LT		 1007}
1008
268157ba
JK		 1009/*
1010 * Free list of dquots
1011 * Dquots are removed from inodes and no new references can be got so we are
1012 * the only ones holding reference
1013 */
1da177e4
LT		 1014static void put_dquot_list(struct list_head *tofree_head)
1015{
1016 struct list_head *act_head;
1017 struct dquot *dquot;
1018
1019 act_head = tofree_head->next;
1da177e4
LT		 1020 while (act_head != tofree_head) {
1021 dquot = list_entry(act_head, struct dquot, dq_free);
1022 act_head = act_head->next;
268157ba
JK		 1023 /* Remove dquot from the list so we won't have problems... */
1024 list_del_init(&dquot->dq_free);
1da177e4
LT		 1025 dqput(dquot);
1026 }
1027}
1028
fb58b731
CH		 1029static void remove_dquot_ref(struct super_block *sb, int type,
1030 struct list_head *tofree_head)
1031{
1032 struct inode *inode;
7af9cce8 1033 int reserved = 0;
fb58b731 1034
74278da9 1035 spin_lock(&sb->s_inode_list_lock);
fb58b731 1036 list_for_each_entry(inode, &sb->s_inodes, i_sb_list) {
aabb8fdb
NP		 1037 /*
1038 * We have to scan also I_NEW inodes because they can already
1039 * have quota pointer initialized. Luckily, we need to touch
1040 * only quota pointers and these have separate locking
b9ba6f94 1041 * (dq_data_lock).
aabb8fdb 1042 */
b9ba6f94 1043 spin_lock(&dq_data_lock);
7af9cce8
DM		 1044 if (!IS_NOQUOTA(inode)) {
1045 if (unlikely(inode_get_rsv_space(inode) > 0))
1046 reserved = 1;
fb58b731 1047 remove_inode_dquot_ref(inode, type, tofree_head);
7af9cce8 1048 }
b9ba6f94 1049 spin_unlock(&dq_data_lock);
fb58b731 1050 }
74278da9 1051 spin_unlock(&sb->s_inode_list_lock);
7af9cce8
DM		 1052#ifdef CONFIG_QUOTA_DEBUG
1053 if (reserved) {
1054 printk(KERN_WARNING "VFS (%s): Writes happened after quota"
1055 " was disabled thus quota information is probably "
1056 "inconsistent. Please run quotacheck(8).\n", sb->s_id);
1057 }
1058#endif
fb58b731
CH		 1059}
1060
1da177e4
LT		 1061/* Gather all references from inodes and drop them */
1062static void drop_dquot_ref(struct super_block *sb, int type)
1063{
1064 LIST_HEAD(tofree_head);
1065
fb58b731 1066 if (sb->dq_op) {
fb58b731 1067 remove_dquot_ref(sb, type, &tofree_head);
b9ba6f94 1068 synchronize_srcu(&dquot_srcu);
fb58b731
CH		 1069 put_dquot_list(&tofree_head);
1070 }
1da177e4
LT		 1071}
1072
12095460 1073static inline void dquot_incr_inodes(struct dquot *dquot, qsize_t number)
1da177e4
LT		 1074{
1075 dquot->dq_dqb.dqb_curinodes += number;
1076}
1077
1078static inline void dquot_incr_space(struct dquot *dquot, qsize_t number)
1079{
1080 dquot->dq_dqb.dqb_curspace += number;
1081}
1082
f18df228
MC		 1083static inline void dquot_resv_space(struct dquot *dquot, qsize_t number)
1084{
1085 dquot->dq_dqb.dqb_rsvspace += number;
1086}
1087
740d9dcd
MC		 1088/*
1089 * Claim reserved quota space
1090 */
0a5a9c72 1091static void dquot_claim_reserved_space(struct dquot *dquot, qsize_t number)
740d9dcd 1092{
0a5a9c72
JK		 1093 if (dquot->dq_dqb.dqb_rsvspace < number) {
1094 WARN_ON_ONCE(1);
1095 number = dquot->dq_dqb.dqb_rsvspace;
1096 }
740d9dcd
MC		 1097 dquot->dq_dqb.dqb_curspace += number;
1098 dquot->dq_dqb.dqb_rsvspace -= number;
1099}
1100
1c8924eb
JK		 1101static void dquot_reclaim_reserved_space(struct dquot *dquot, qsize_t number)
1102{
1103 if (WARN_ON_ONCE(dquot->dq_dqb.dqb_curspace < number))
1104 number = dquot->dq_dqb.dqb_curspace;
1105 dquot->dq_dqb.dqb_rsvspace += number;
1106 dquot->dq_dqb.dqb_curspace -= number;
1107}
1108
740d9dcd
MC		 1109static inline
1110void dquot_free_reserved_space(struct dquot *dquot, qsize_t number)
1111{
0a5a9c72
JK		 1112 if (dquot->dq_dqb.dqb_rsvspace >= number)
1113 dquot->dq_dqb.dqb_rsvspace -= number;
1114 else {
1115 WARN_ON_ONCE(1);
1116 dquot->dq_dqb.dqb_rsvspace = 0;
1117 }
740d9dcd
MC		 1118}
1119
7a2435d8 1120static void dquot_decr_inodes(struct dquot *dquot, qsize_t number)
1da177e4 1121{
db49d2df
JK		 1122 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE ||
1123 dquot->dq_dqb.dqb_curinodes >= number)
1da177e4
LT		 1124 dquot->dq_dqb.dqb_curinodes -= number;
1125 else
1126 dquot->dq_dqb.dqb_curinodes = 0;
1127 if (dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit)
e008bb61 1128 dquot->dq_dqb.dqb_itime = (time64_t) 0;
1da177e4
LT		 1129 clear_bit(DQ_INODES_B, &dquot->dq_flags);
1130}
1131
7a2435d8 1132static void dquot_decr_space(struct dquot *dquot, qsize_t number)
1da177e4 1133{
db49d2df
JK		 1134 if (sb_dqopt(dquot->dq_sb)->flags & DQUOT_NEGATIVE_USAGE ||
1135 dquot->dq_dqb.dqb_curspace >= number)
1da177e4
LT		 1136 dquot->dq_dqb.dqb_curspace -= number;
1137 else
1138 dquot->dq_dqb.dqb_curspace = 0;
12095460 1139 if (dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit)
e008bb61 1140 dquot->dq_dqb.dqb_btime = (time64_t) 0;
1da177e4
LT		 1141 clear_bit(DQ_BLKS_B, &dquot->dq_flags);
1142}
1143
bf097aaf
JK		 1144struct dquot_warn {
1145 struct super_block *w_sb;
7b9c7321 1146 struct kqid w_dq_id;
bf097aaf
JK		 1147 short w_type;
1148};
1149
c525460e
JK		 1150static int warning_issued(struct dquot *dquot, const int warntype)
1151{
1152 int flag = (warntype == QUOTA_NL_BHARDWARN ||
1153 warntype == QUOTA_NL_BSOFTLONGWARN) ? DQ_BLKS_B :
1154 ((warntype == QUOTA_NL_IHARDWARN ||
1155 warntype == QUOTA_NL_ISOFTLONGWARN) ? DQ_INODES_B : 0);
1156
1157 if (!flag)
1158 return 0;
1159 return test_and_set_bit(flag, &dquot->dq_flags);
1160}
1161
8e893469 1162#ifdef CONFIG_PRINT_QUOTA_WARNING
1da177e4
LT		 1163static int flag_print_warnings = 1;
1164
bf097aaf 1165static int need_print_warning(struct dquot_warn *warn)
1da177e4
LT		 1166{
1167 if (!flag_print_warnings)
1168 return 0;
1169
7b9c7321 1170 switch (warn->w_dq_id.type) {
1da177e4 1171 case USRQUOTA:
1a06d420 1172 return uid_eq(current_fsuid(), warn->w_dq_id.uid);
1da177e4 1173 case GRPQUOTA:
7b9c7321 1174 return in_group_p(warn->w_dq_id.gid);
847aac64
LX		 1175 case PRJQUOTA:
1176 return 1;
1da177e4
LT		 1177 }
1178 return 0;
1179}
1180
1da177e4 1181/* Print warning to user which exceeded quota */
bf097aaf 1182static void print_warning(struct dquot_warn *warn)
1da177e4
LT		 1183{
1184 char *msg = NULL;
24ec839c 1185 struct tty_struct *tty;
bf097aaf 1186 int warntype = warn->w_type;
1da177e4 1187
657d3bfa
JK		 1188 if (warntype == QUOTA_NL_IHARDBELOW ||
1189 warntype == QUOTA_NL_ISOFTBELOW ||
1190 warntype == QUOTA_NL_BHARDBELOW ||
bf097aaf 1191 warntype == QUOTA_NL_BSOFTBELOW || !need_print_warning(warn))
1da177e4
LT		 1192 return;
1193
24ec839c
PZ		 1194 tty = get_current_tty();
1195 if (!tty)
452a00d2 1196 return;
bf097aaf 1197 tty_write_message(tty, warn->w_sb->s_id);
8e893469 1198 if (warntype == QUOTA_NL_ISOFTWARN || warntype == QUOTA_NL_BSOFTWARN)
24ec839c 1199 tty_write_message(tty, ": warning, ");
1da177e4 1200 else
24ec839c 1201 tty_write_message(tty, ": write failed, ");
7b9c7321 1202 tty_write_message(tty, quotatypes[warn->w_dq_id.type]);
1da177e4 1203 switch (warntype) {
8e893469 1204 case QUOTA_NL_IHARDWARN:
1da177e4
LT		 1205 msg = " file limit reached.\r\n";
1206 break;
8e893469 1207 case QUOTA_NL_ISOFTLONGWARN:
1da177e4
LT		 1208 msg = " file quota exceeded too long.\r\n";
1209 break;
8e893469 1210 case QUOTA_NL_ISOFTWARN:
1da177e4
LT		 1211 msg = " file quota exceeded.\r\n";
1212 break;
8e893469 1213 case QUOTA_NL_BHARDWARN:
1da177e4
LT		 1214 msg = " block limit reached.\r\n";
1215 break;
8e893469 1216 case QUOTA_NL_BSOFTLONGWARN:
1da177e4
LT		 1217 msg = " block quota exceeded too long.\r\n";
1218 break;
8e893469 1219 case QUOTA_NL_BSOFTWARN:
1da177e4
LT		 1220 msg = " block quota exceeded.\r\n";
1221 break;
1222 }
24ec839c 1223 tty_write_message(tty, msg);
452a00d2 1224 tty_kref_put(tty);
1da177e4 1225}
8e893469
JK		 1226#endif
1227
bf097aaf
JK		 1228static void prepare_warning(struct dquot_warn *warn, struct dquot *dquot,
1229 int warntype)
1230{
1231 if (warning_issued(dquot, warntype))
1232 return;
1233 warn->w_type = warntype;
1234 warn->w_sb = dquot->dq_sb;
1235 warn->w_dq_id = dquot->dq_id;
bf097aaf
JK		 1236}
1237
f18df228
MC		 1238/*
1239 * Write warnings to the console and send warning messages over netlink.
1240 *
bf097aaf 1241 * Note that this function can call into tty and networking code.
f18df228 1242 */
bf097aaf 1243static void flush_warnings(struct dquot_warn *warn)
1da177e4
LT		 1244{
1245 int i;
1246
86e931a3 1247 for (i = 0; i < MAXQUOTAS; i++) {
bf097aaf
JK		 1248 if (warn[i].w_type == QUOTA_NL_NOWARN)
1249 continue;
8e893469 1250#ifdef CONFIG_PRINT_QUOTA_WARNING
bf097aaf 1251 print_warning(&warn[i]);
8e893469 1252#endif
7b9c7321 1253 quota_send_warning(warn[i].w_dq_id,
bf097aaf 1254 warn[i].w_sb->s_dev, warn[i].w_type);
86e931a3 1255 }
1da177e4
LT		 1256}
1257
7a2435d8 1258static int ignore_hardlimit(struct dquot *dquot)
1da177e4 1259{
4c376dca 1260 struct mem_dqinfo *info = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type];
1da177e4
LT		 1261
1262 return capable(CAP_SYS_RESOURCE) &&
268157ba 1263 (info->dqi_format->qf_fmt_id != QFMT_VFS_OLD ||
9c45101e 1264 !(info->dqi_flags & DQF_ROOT_SQUASH));
1da177e4
LT		 1265}
1266
1267/* needs dq_data_lock */
bf097aaf
JK		 1268static int check_idq(struct dquot *dquot, qsize_t inodes,
1269 struct dquot_warn *warn)
1da177e4 1270{
268157ba
JK		 1271 qsize_t newinodes = dquot->dq_dqb.dqb_curinodes + inodes;
1272
4c376dca 1273 if (!sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_id.type) ||
f55abc0f 1274 test_bit(DQ_FAKE_B, &dquot->dq_flags))
efd8f0e6 1275 return 0;
1da177e4
LT		 1276
1277 if (dquot->dq_dqb.dqb_ihardlimit &&
268157ba 1278 newinodes > dquot->dq_dqb.dqb_ihardlimit &&
1da177e4 1279 !ignore_hardlimit(dquot)) {
bf097aaf 1280 prepare_warning(warn, dquot, QUOTA_NL_IHARDWARN);
efd8f0e6 1281 return -EDQUOT;
1da177e4
LT		 1282 }
1283
1284 if (dquot->dq_dqb.dqb_isoftlimit &&
268157ba
JK		 1285 newinodes > dquot->dq_dqb.dqb_isoftlimit &&
1286 dquot->dq_dqb.dqb_itime &&
e008bb61 1287 ktime_get_real_seconds() >= dquot->dq_dqb.dqb_itime &&
1da177e4 1288 !ignore_hardlimit(dquot)) {
bf097aaf 1289 prepare_warning(warn, dquot, QUOTA_NL_ISOFTLONGWARN);
efd8f0e6 1290 return -EDQUOT;
1da177e4
LT		 1291 }
1292
1293 if (dquot->dq_dqb.dqb_isoftlimit &&
268157ba 1294 newinodes > dquot->dq_dqb.dqb_isoftlimit &&
1da177e4 1295 dquot->dq_dqb.dqb_itime == 0) {
bf097aaf 1296 prepare_warning(warn, dquot, QUOTA_NL_ISOFTWARN);
e008bb61 1297 dquot->dq_dqb.dqb_itime = ktime_get_real_seconds() +
4c376dca 1298 sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type].dqi_igrace;
1da177e4
LT		 1299 }
1300
efd8f0e6 1301 return 0;
1da177e4
LT		 1302}
1303
1304/* needs dq_data_lock */
bf097aaf
JK		 1305static int check_bdq(struct dquot *dquot, qsize_t space, int prealloc,
1306 struct dquot_warn *warn)
1da177e4 1307{
f18df228 1308 qsize_t tspace;
268157ba 1309 struct super_block *sb = dquot->dq_sb;
f18df228 1310
4c376dca 1311 if (!sb_has_quota_limits_enabled(sb, dquot->dq_id.type) ||
f55abc0f 1312 test_bit(DQ_FAKE_B, &dquot->dq_flags))
efd8f0e6 1313 return 0;
1da177e4 1314
f18df228
MC		 1315 tspace = dquot->dq_dqb.dqb_curspace + dquot->dq_dqb.dqb_rsvspace
1316 + space;
1317
1da177e4 1318 if (dquot->dq_dqb.dqb_bhardlimit &&
f18df228 1319 tspace > dquot->dq_dqb.dqb_bhardlimit &&
1da177e4
LT		 1320 !ignore_hardlimit(dquot)) {
1321 if (!prealloc)
bf097aaf 1322 prepare_warning(warn, dquot, QUOTA_NL_BHARDWARN);
efd8f0e6 1323 return -EDQUOT;
1da177e4
LT		 1324 }
1325
1326 if (dquot->dq_dqb.dqb_bsoftlimit &&
f18df228 1327 tspace > dquot->dq_dqb.dqb_bsoftlimit &&
268157ba 1328 dquot->dq_dqb.dqb_btime &&
e008bb61 1329 ktime_get_real_seconds() >= dquot->dq_dqb.dqb_btime &&
1da177e4
LT		 1330 !ignore_hardlimit(dquot)) {
1331 if (!prealloc)
bf097aaf 1332 prepare_warning(warn, dquot, QUOTA_NL_BSOFTLONGWARN);
efd8f0e6 1333 return -EDQUOT;
1da177e4
LT		 1334 }
1335
1336 if (dquot->dq_dqb.dqb_bsoftlimit &&
f18df228 1337 tspace > dquot->dq_dqb.dqb_bsoftlimit &&
1da177e4
LT		 1338 dquot->dq_dqb.dqb_btime == 0) {
1339 if (!prealloc) {
bf097aaf 1340 prepare_warning(warn, dquot, QUOTA_NL_BSOFTWARN);
e008bb61 1341 dquot->dq_dqb.dqb_btime = ktime_get_real_seconds() +
4c376dca 1342 sb_dqopt(sb)->info[dquot->dq_id.type].dqi_bgrace;
1da177e4
LT		 1343 }
1344 else
1345 /*
1346 * We don't allow preallocation to exceed softlimit so exceeding will
1347 * be always printed
1348 */
efd8f0e6 1349 return -EDQUOT;
1da177e4
LT		 1350 }
1351
efd8f0e6 1352 return 0;
1da177e4
LT		 1353}
1354
12095460 1355static int info_idq_free(struct dquot *dquot, qsize_t inodes)
657d3bfa 1356{
268157ba
JK		 1357 qsize_t newinodes;
1358
657d3bfa 1359 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) ||
f55abc0f 1360 dquot->dq_dqb.dqb_curinodes <= dquot->dq_dqb.dqb_isoftlimit ||
4c376dca 1361 !sb_has_quota_limits_enabled(dquot->dq_sb, dquot->dq_id.type))
657d3bfa
JK		 1362 return QUOTA_NL_NOWARN;
1363
268157ba
JK		 1364 newinodes = dquot->dq_dqb.dqb_curinodes - inodes;
1365 if (newinodes <= dquot->dq_dqb.dqb_isoftlimit)
657d3bfa
JK		 1366 return QUOTA_NL_ISOFTBELOW;
1367 if (dquot->dq_dqb.dqb_curinodes >= dquot->dq_dqb.dqb_ihardlimit &&
268157ba 1368 newinodes < dquot->dq_dqb.dqb_ihardlimit)
657d3bfa
JK		 1369 return QUOTA_NL_IHARDBELOW;
1370 return QUOTA_NL_NOWARN;
1371}
1372
1373static int info_bdq_free(struct dquot *dquot, qsize_t space)
1374{
1375 if (test_bit(DQ_FAKE_B, &dquot->dq_flags) ||
12095460 1376 dquot->dq_dqb.dqb_curspace <= dquot->dq_dqb.dqb_bsoftlimit)
657d3bfa
JK		 1377 return QUOTA_NL_NOWARN;
1378
12095460 1379 if (dquot->dq_dqb.dqb_curspace - space <= dquot->dq_dqb.dqb_bsoftlimit)
657d3bfa 1380 return QUOTA_NL_BSOFTBELOW;
12095460
JK		 1381 if (dquot->dq_dqb.dqb_curspace >= dquot->dq_dqb.dqb_bhardlimit &&
1382 dquot->dq_dqb.dqb_curspace - space < dquot->dq_dqb.dqb_bhardlimit)
657d3bfa
JK		 1383 return QUOTA_NL_BHARDBELOW;
1384 return QUOTA_NL_NOWARN;
1385}
0a5a9c72 1386
189eef59
CH		 1387static int dquot_active(const struct inode *inode)
1388{
1389 struct super_block *sb = inode->i_sb;
1390
1391 if (IS_NOQUOTA(inode))
1392 return 0;
1393 return sb_any_quota_loaded(sb) & ~sb_any_quota_suspended(sb);
1394}
1395
1da177e4 1396/*
871a2931
CH		 1397 * Initialize quota pointers in inode
1398 *
871a2931
CH		 1399 * It is better to call this function outside of any transaction as it
1400 * might need a lot of space in journal for dquot structure allocation.
1da177e4 1401 */
6184fc0b 1402static int __dquot_initialize(struct inode *inode, int type)
1da177e4 1403{
1ea06bec 1404 int cnt, init_needed = 0;
ab73ef46 1405 struct dquot **dquots, *got[MAXQUOTAS] = {};
cc33412f 1406 struct super_block *sb = inode->i_sb;
0a5a9c72 1407 qsize_t rsv;
6184fc0b 1408 int ret = 0;
1da177e4 1409
189eef59 1410 if (!dquot_active(inode))
6184fc0b 1411 return 0;
cc33412f 1412
5bcd3b6f
KK		 1413 dquots = i_dquot(inode);
1414
cc33412f
JK		 1415 /* First get references to structures we might need. */
1416 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
aca645a6 1417 struct kqid qid;
847aac64
LX		 1418 kprojid_t projid;
1419 int rc;
6184fc0b 1420 struct dquot *dquot;
847aac64 1421
cc33412f
JK		 1422 if (type != -1 && cnt != type)
1423 continue;
1ea06bec
NY		 1424 /*
1425 * The i_dquot should have been initialized in most cases,
1426 * we check it without locking here to avoid unnecessary
1427 * dqget()/dqput() calls.
1428 */
5bcd3b6f 1429 if (dquots[cnt])
1ea06bec 1430 continue;
847aac64
LX		 1431
1432 if (!sb_has_quota_active(sb, cnt))
1433 continue;
1434
1ea06bec
NY		 1435 init_needed = 1;
1436
cc33412f
JK		 1437 switch (cnt) {
1438 case USRQUOTA:
aca645a6 1439 qid = make_kqid_uid(inode->i_uid);
cc33412f
JK		 1440 break;
1441 case GRPQUOTA:
aca645a6 1442 qid = make_kqid_gid(inode->i_gid);
cc33412f 1443 break;
847aac64
LX		 1444 case PRJQUOTA:
1445 rc = inode->i_sb->dq_op->get_projid(inode, &projid);
1446 if (rc)
1447 continue;
1448 qid = make_kqid_projid(projid);
1449 break;
cc33412f 1450 }
6184fc0b
JK		 1451 dquot = dqget(sb, qid);
1452 if (IS_ERR(dquot)) {
1453 /* We raced with somebody turning quotas off... */
1454 if (PTR_ERR(dquot) != -ESRCH) {
1455 ret = PTR_ERR(dquot);
1456 goto out_put;
1457 }
1458 dquot = NULL;
1459 }
1460 got[cnt] = dquot;
cc33412f
JK		 1461 }
1462
1ea06bec
NY		 1463 /* All required i_dquot has been initialized */
1464 if (!init_needed)
6184fc0b 1465 return 0;
1ea06bec 1466
b9ba6f94 1467 spin_lock(&dq_data_lock);
1da177e4 1468 if (IS_NOQUOTA(inode))
6184fc0b 1469 goto out_lock;
1da177e4
LT		 1470 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1471 if (type != -1 && cnt != type)
1472 continue;
cc33412f
JK		 1473 /* Avoid races with quotaoff() */
1474 if (!sb_has_quota_active(sb, cnt))
1475 continue;
4408ea41
JK		 1476 /* We could race with quotaon or dqget() could have failed */
1477 if (!got[cnt])
1478 continue;
5bcd3b6f
KK		 1479 if (!dquots[cnt]) {
1480 dquots[cnt] = got[cnt];
dd6f3c6d 1481 got[cnt] = NULL;
0a5a9c72
JK		 1482 /*
1483 * Make quota reservation system happy if someone
1484 * did a write before quota was turned on
1485 */
1486 rsv = inode_get_rsv_space(inode);
b9ba6f94 1487 if (unlikely(rsv))
5bcd3b6f 1488 dquot_resv_space(dquots[cnt], rsv);
1da177e4
LT		 1489 }
1490 }
6184fc0b 1491out_lock:
b9ba6f94 1492 spin_unlock(&dq_data_lock);
6184fc0b 1493out_put:
cc33412f 1494 /* Drop unused references */
dc52dd3a 1495 dqput_all(got);
6184fc0b
JK		 1496
1497 return ret;
871a2931
CH		 1498}
1499
6184fc0b 1500int dquot_initialize(struct inode *inode)
871a2931 1501{
6184fc0b 1502 return __dquot_initialize(inode, -1);
1da177e4 1503}
08d0350c 1504EXPORT_SYMBOL(dquot_initialize);
1da177e4 1505
b8cb5a54
TE		 1506bool dquot_initialize_needed(struct inode *inode)
1507{
1508 struct dquot **dquots;
1509 int i;
1510
1511 if (!dquot_active(inode))
1512 return false;
1513
1514 dquots = i_dquot(inode);
1515 for (i = 0; i < MAXQUOTAS; i++)
1516 if (!dquots[i] && sb_has_quota_active(inode->i_sb, i))
1517 return true;
1518 return false;
1519}
1520EXPORT_SYMBOL(dquot_initialize_needed);
1521
1da177e4 1522/*
b9ba6f94
NY		 1523 * Release all quotas referenced by inode.
1524 *
1525 * This function only be called on inode free or converting
1526 * a file to quota file, no other users for the i_dquot in
1527 * both cases, so we needn't call synchronize_srcu() after
1528 * clearing i_dquot.
1da177e4 1529 */
9f754758 1530static void __dquot_drop(struct inode *inode)
1da177e4
LT		 1531{
1532 int cnt;
5bcd3b6f 1533 struct dquot **dquots = i_dquot(inode);
cc33412f 1534 struct dquot *put[MAXQUOTAS];
1da177e4 1535
b9ba6f94 1536 spin_lock(&dq_data_lock);
1da177e4 1537 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
5bcd3b6f
KK		 1538 put[cnt] = dquots[cnt];
1539 dquots[cnt] = NULL;
1da177e4 1540 }
b9ba6f94 1541 spin_unlock(&dq_data_lock);
dc52dd3a 1542 dqput_all(put);
1da177e4
LT		 1543}
1544
9f754758
CH		 1545void dquot_drop(struct inode *inode)
1546{
5bcd3b6f 1547 struct dquot * const *dquots;
9f754758
CH		 1548 int cnt;
1549
1550 if (IS_NOQUOTA(inode))
1551 return;
1552
1553 /*
1554 * Test before calling to rule out calls from proc and such
1555 * where we are not allowed to block. Note that this is
1556 * actually reliable test even without the lock - the caller
1557 * must assure that nobody can come after the DQUOT_DROP and
1558 * add quota pointers back anyway.
1559 */
5bcd3b6f 1560 dquots = i_dquot(inode);
9f754758 1561 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
5bcd3b6f 1562 if (dquots[cnt])
9f754758
CH		 1563 break;
1564 }
1565
1566 if (cnt < MAXQUOTAS)
1567 __dquot_drop(inode);
1568}
1569EXPORT_SYMBOL(dquot_drop);
b85f4b87 1570
fd8fbfc1
DM		 1571/*
1572 * inode_reserved_space is managed internally by quota, and protected by
1573 * i_lock similar to i_blocks+i_bytes.
1574 */
1575static qsize_t *inode_reserved_space(struct inode * inode)
1576{
1577 /* Filesystem must explicitly define it's own method in order to use
1578 * quota reservation interface */
1579 BUG_ON(!inode->i_sb->dq_op->get_reserved_space);
1580 return inode->i_sb->dq_op->get_reserved_space(inode);
1581}
1582
c469070a 1583void inode_add_rsv_space(struct inode *inode, qsize_t number)
fd8fbfc1
DM		 1584{
1585 spin_lock(&inode->i_lock);
1586 *inode_reserved_space(inode) += number;
1587 spin_unlock(&inode->i_lock);
1588}
c469070a 1589EXPORT_SYMBOL(inode_add_rsv_space);
fd8fbfc1 1590
c469070a 1591void inode_claim_rsv_space(struct inode *inode, qsize_t number)
fd8fbfc1
DM		 1592{
1593 spin_lock(&inode->i_lock);
1594 *inode_reserved_space(inode) -= number;
1595 __inode_add_bytes(inode, number);
1596 spin_unlock(&inode->i_lock);
1597}
c469070a 1598EXPORT_SYMBOL(inode_claim_rsv_space);
fd8fbfc1 1599
1c8924eb
JK		 1600void inode_reclaim_rsv_space(struct inode *inode, qsize_t number)
1601{
1602 spin_lock(&inode->i_lock);
1603 *inode_reserved_space(inode) += number;
1604 __inode_sub_bytes(inode, number);
1605 spin_unlock(&inode->i_lock);
1606}
1607EXPORT_SYMBOL(inode_reclaim_rsv_space);
1608
c469070a 1609void inode_sub_rsv_space(struct inode *inode, qsize_t number)
fd8fbfc1
DM		 1610{
1611 spin_lock(&inode->i_lock);
1612 *inode_reserved_space(inode) -= number;
1613 spin_unlock(&inode->i_lock);
1614}
c469070a 1615EXPORT_SYMBOL(inode_sub_rsv_space);
fd8fbfc1
DM		 1616
1617static qsize_t inode_get_rsv_space(struct inode *inode)
1618{
1619 qsize_t ret;
05b5d898
JK		 1620
1621 if (!inode->i_sb->dq_op->get_reserved_space)
1622 return 0;
fd8fbfc1
DM		 1623 spin_lock(&inode->i_lock);
1624 ret = *inode_reserved_space(inode);
1625 spin_unlock(&inode->i_lock);
1626 return ret;
1627}
1628
1629static void inode_incr_space(struct inode *inode, qsize_t number,
1630 int reserve)
1631{
1632 if (reserve)
1633 inode_add_rsv_space(inode, number);
1634 else
1635 inode_add_bytes(inode, number);
1636}
1637
1638static void inode_decr_space(struct inode *inode, qsize_t number, int reserve)
1639{
1640 if (reserve)
1641 inode_sub_rsv_space(inode, number);
1642 else
1643 inode_sub_bytes(inode, number);
1644}
1645
1da177e4 1646/*
5dd4056d
CH		 1647 * This functions updates i_blocks+i_bytes fields and quota information
1648 * (together with appropriate checks).
1649 *
1650 * NOTE: We absolutely rely on the fact that caller dirties the inode
1651 * (usually helpers in quotaops.h care about this) and holds a handle for
1652 * the current transaction so that dquot write and inode write go into the
1653 * same transaction.
1da177e4
LT		 1654 */
1655
1656/*
1657 * This operation can block, but only after everything is updated
1658 */
56246f9a 1659int __dquot_alloc_space(struct inode *inode, qsize_t number, int flags)
1da177e4 1660{
b9ba6f94 1661 int cnt, ret = 0, index;
bf097aaf 1662 struct dquot_warn warn[MAXQUOTAS];
56246f9a 1663 int reserve = flags & DQUOT_SPACE_RESERVE;
5bcd3b6f 1664 struct dquot **dquots;
1da177e4 1665
189eef59 1666 if (!dquot_active(inode)) {
fd8fbfc1
DM		 1667 inode_incr_space(inode, number, reserve);
1668 goto out;
1669 }
1670
1da177e4 1671 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
bf097aaf 1672 warn[cnt].w_type = QUOTA_NL_NOWARN;
1da177e4 1673
5bcd3b6f 1674 dquots = i_dquot(inode);
b9ba6f94 1675 index = srcu_read_lock(&dquot_srcu);
1da177e4
LT		 1676 spin_lock(&dq_data_lock);
1677 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
bf097aaf 1678 if (!dquots[cnt])
1da177e4 1679 continue;
bf097aaf
JK		 1680 ret = check_bdq(dquots[cnt], number,
1681 !(flags & DQUOT_SPACE_WARN), &warn[cnt]);
1682 if (ret && !(flags & DQUOT_SPACE_NOFAIL)) {
fd8fbfc1
DM		 1683 spin_unlock(&dq_data_lock);
1684 goto out_flush_warn;
f18df228 1685 }
1da177e4
LT		 1686 }
1687 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
bf097aaf 1688 if (!dquots[cnt])
1da177e4 1689 continue;
f18df228 1690 if (reserve)
bf097aaf 1691 dquot_resv_space(dquots[cnt], number);
f18df228 1692 else
bf097aaf 1693 dquot_incr_space(dquots[cnt], number);
1da177e4 1694 }
fd8fbfc1 1695 inode_incr_space(inode, number, reserve);
1da177e4 1696 spin_unlock(&dq_data_lock);
f18df228 1697
fd8fbfc1
DM		 1698 if (reserve)
1699 goto out_flush_warn;
bf097aaf 1700 mark_all_dquot_dirty(dquots);
fd8fbfc1 1701out_flush_warn:
b9ba6f94 1702 srcu_read_unlock(&dquot_srcu, index);
bf097aaf 1703 flush_warnings(warn);
f18df228
MC		 1704out:
1705 return ret;
1706}
5dd4056d 1707EXPORT_SYMBOL(__dquot_alloc_space);
1da177e4
LT		 1708
1709/*
1710 * This operation can block, but only after everything is updated
1711 */
6bab3596 1712int dquot_alloc_inode(struct inode *inode)
1da177e4 1713{
b9ba6f94 1714 int cnt, ret = 0, index;
bf097aaf 1715 struct dquot_warn warn[MAXQUOTAS];
5bcd3b6f 1716 struct dquot * const *dquots;
1da177e4 1717
189eef59 1718 if (!dquot_active(inode))
63936dda 1719 return 0;
1da177e4 1720 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
bf097aaf 1721 warn[cnt].w_type = QUOTA_NL_NOWARN;
b9ba6f94 1722
5bcd3b6f 1723 dquots = i_dquot(inode);
b9ba6f94 1724 index = srcu_read_lock(&dquot_srcu);
1da177e4
LT		 1725 spin_lock(&dq_data_lock);
1726 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
bf097aaf 1727 if (!dquots[cnt])
1da177e4 1728 continue;
bf097aaf 1729 ret = check_idq(dquots[cnt], 1, &warn[cnt]);
efd8f0e6 1730 if (ret)
1da177e4
LT		 1731 goto warn_put_all;
1732 }
1733
1734 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
bf097aaf 1735 if (!dquots[cnt])
1da177e4 1736 continue;
bf097aaf 1737 dquot_incr_inodes(dquots[cnt], 1);
1da177e4 1738 }
efd8f0e6 1739
1da177e4
LT		 1740warn_put_all:
1741 spin_unlock(&dq_data_lock);
63936dda 1742 if (ret == 0)
bf097aaf 1743 mark_all_dquot_dirty(dquots);
b9ba6f94 1744 srcu_read_unlock(&dquot_srcu, index);
bf097aaf 1745 flush_warnings(warn);
1da177e4
LT		 1746 return ret;
1747}
08d0350c 1748EXPORT_SYMBOL(dquot_alloc_inode);
1da177e4 1749
5dd4056d
CH		 1750/*
1751 * Convert in-memory reserved quotas to real consumed quotas
1752 */
1753int dquot_claim_space_nodirty(struct inode *inode, qsize_t number)
740d9dcd 1754{
5bcd3b6f 1755 struct dquot **dquots;
b9ba6f94 1756 int cnt, index;
740d9dcd 1757
189eef59 1758 if (!dquot_active(inode)) {
fd8fbfc1 1759 inode_claim_rsv_space(inode, number);
5dd4056d 1760 return 0;
740d9dcd
MC		 1761 }
1762
5bcd3b6f 1763 dquots = i_dquot(inode);
b9ba6f94 1764 index = srcu_read_lock(&dquot_srcu);
740d9dcd
MC		 1765 spin_lock(&dq_data_lock);
1766 /* Claim reserved quotas to allocated quotas */
1767 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
5bcd3b6f
KK		 1768 if (dquots[cnt])
1769 dquot_claim_reserved_space(dquots[cnt], number);
740d9dcd
MC		 1770 }
1771 /* Update inode bytes */
fd8fbfc1 1772 inode_claim_rsv_space(inode, number);
740d9dcd 1773 spin_unlock(&dq_data_lock);
5bcd3b6f 1774 mark_all_dquot_dirty(dquots);
b9ba6f94 1775 srcu_read_unlock(&dquot_srcu, index);
5dd4056d 1776 return 0;
740d9dcd 1777}
5dd4056d 1778EXPORT_SYMBOL(dquot_claim_space_nodirty);
740d9dcd 1779
1c8924eb
JK		 1780/*
1781 * Convert allocated space back to in-memory reserved quotas
1782 */
1783void dquot_reclaim_space_nodirty(struct inode *inode, qsize_t number)
1784{
5bcd3b6f 1785 struct dquot **dquots;
b9ba6f94 1786 int cnt, index;
1c8924eb
JK		 1787
1788 if (!dquot_active(inode)) {
1789 inode_reclaim_rsv_space(inode, number);
1790 return;
1791 }
1792
5bcd3b6f 1793 dquots = i_dquot(inode);
b9ba6f94 1794 index = srcu_read_lock(&dquot_srcu);
1c8924eb
JK		 1795 spin_lock(&dq_data_lock);
1796 /* Claim reserved quotas to allocated quotas */
1797 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
5bcd3b6f
KK		 1798 if (dquots[cnt])
1799 dquot_reclaim_reserved_space(dquots[cnt], number);
1c8924eb
JK		 1800 }
1801 /* Update inode bytes */
1802 inode_reclaim_rsv_space(inode, number);
1803 spin_unlock(&dq_data_lock);
5bcd3b6f 1804 mark_all_dquot_dirty(dquots);
b9ba6f94 1805 srcu_read_unlock(&dquot_srcu, index);
1c8924eb
JK		 1806 return;
1807}
1808EXPORT_SYMBOL(dquot_reclaim_space_nodirty);
1809
1da177e4
LT		 1810/*
1811 * This operation can block, but only after everything is updated
1812 */
56246f9a 1813void __dquot_free_space(struct inode *inode, qsize_t number, int flags)
1da177e4
LT		 1814{
1815 unsigned int cnt;
bf097aaf 1816 struct dquot_warn warn[MAXQUOTAS];
5bcd3b6f 1817 struct dquot **dquots;
b9ba6f94 1818 int reserve = flags & DQUOT_SPACE_RESERVE, index;
1da177e4 1819
189eef59 1820 if (!dquot_active(inode)) {
fd8fbfc1 1821 inode_decr_space(inode, number, reserve);
5dd4056d 1822 return;
1da177e4 1823 }
657d3bfa 1824
5bcd3b6f 1825 dquots = i_dquot(inode);
b9ba6f94 1826 index = srcu_read_lock(&dquot_srcu);
1da177e4
LT		 1827 spin_lock(&dq_data_lock);
1828 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
bf097aaf
JK		 1829 int wtype;
1830
1831 warn[cnt].w_type = QUOTA_NL_NOWARN;
1832 if (!dquots[cnt])
1da177e4 1833 continue;
bf097aaf
JK		 1834 wtype = info_bdq_free(dquots[cnt], number);
1835 if (wtype != QUOTA_NL_NOWARN)
1836 prepare_warning(&warn[cnt], dquots[cnt], wtype);
fd8fbfc1 1837 if (reserve)
bf097aaf 1838 dquot_free_reserved_space(dquots[cnt], number);
fd8fbfc1 1839 else
bf097aaf 1840 dquot_decr_space(dquots[cnt], number);
1da177e4 1841 }
fd8fbfc1 1842 inode_decr_space(inode, number, reserve);
1da177e4 1843 spin_unlock(&dq_data_lock);
fd8fbfc1
DM		 1844
1845 if (reserve)
1846 goto out_unlock;
bf097aaf 1847 mark_all_dquot_dirty(dquots);
fd8fbfc1 1848out_unlock:
b9ba6f94 1849 srcu_read_unlock(&dquot_srcu, index);
bf097aaf 1850 flush_warnings(warn);
fd8fbfc1 1851}
5dd4056d 1852EXPORT_SYMBOL(__dquot_free_space);
fd8fbfc1 1853
1da177e4
LT		 1854/*
1855 * This operation can block, but only after everything is updated
1856 */
6bab3596 1857void dquot_free_inode(struct inode *inode)
1da177e4
LT		 1858{
1859 unsigned int cnt;
bf097aaf 1860 struct dquot_warn warn[MAXQUOTAS];
5bcd3b6f 1861 struct dquot * const *dquots;
b9ba6f94 1862 int index;
1da177e4 1863
189eef59 1864 if (!dquot_active(inode))
63936dda 1865 return;
657d3bfa 1866
5bcd3b6f 1867 dquots = i_dquot(inode);
b9ba6f94 1868 index = srcu_read_lock(&dquot_srcu);
1da177e4
LT		 1869 spin_lock(&dq_data_lock);
1870 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
bf097aaf
JK		 1871 int wtype;
1872
1873 warn[cnt].w_type = QUOTA_NL_NOWARN;
1874 if (!dquots[cnt])
1da177e4 1875 continue;
bf097aaf
JK		 1876 wtype = info_idq_free(dquots[cnt], 1);
1877 if (wtype != QUOTA_NL_NOWARN)
1878 prepare_warning(&warn[cnt], dquots[cnt], wtype);
1879 dquot_decr_inodes(dquots[cnt], 1);
1da177e4
LT		 1880 }
1881 spin_unlock(&dq_data_lock);
bf097aaf 1882 mark_all_dquot_dirty(dquots);
b9ba6f94 1883 srcu_read_unlock(&dquot_srcu, index);
bf097aaf 1884 flush_warnings(warn);
1da177e4 1885}
08d0350c 1886EXPORT_SYMBOL(dquot_free_inode);
1da177e4
LT		 1887
1888/*
1889 * Transfer the number of inode and blocks from one diskquota to an other.
bc8e5f07
JK		 1890 * On success, dquot references in transfer_to are consumed and references
1891 * to original dquots that need to be released are placed there. On failure,
1892 * references are kept untouched.
1da177e4
LT		 1893 *
1894 * This operation can block, but only after everything is updated
1895 * A transaction must be started when entering this function.
bc8e5f07 1896 *
b9ba6f94
NY		 1897 * We are holding reference on transfer_from & transfer_to, no need to
1898 * protect them by srcu_read_lock().
1da177e4 1899 */
bc8e5f07 1900int __dquot_transfer(struct inode *inode, struct dquot **transfer_to)
1da177e4 1901{
740d9dcd
MC		 1902 qsize_t space, cur_space;
1903 qsize_t rsv_space = 0;
7a9ca53a 1904 qsize_t inode_usage = 1;
bc8e5f07 1905 struct dquot *transfer_from[MAXQUOTAS] = {};
efd8f0e6 1906 int cnt, ret = 0;
9e32784b 1907 char is_valid[MAXQUOTAS] = {};
bf097aaf
JK		 1908 struct dquot_warn warn_to[MAXQUOTAS];
1909 struct dquot_warn warn_from_inodes[MAXQUOTAS];
1910 struct dquot_warn warn_from_space[MAXQUOTAS];
1da177e4 1911
1da177e4 1912 if (IS_NOQUOTA(inode))
efd8f0e6 1913 return 0;
7a9ca53a
TE		 1914
1915 if (inode->i_sb->dq_op->get_inode_usage) {
1916 ret = inode->i_sb->dq_op->get_inode_usage(inode, &inode_usage);
1917 if (ret)
1918 return ret;
1919 }
1920
cc33412f 1921 /* Initialize the arrays */
bf097aaf
JK		 1922 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
1923 warn_to[cnt].w_type = QUOTA_NL_NOWARN;
1924 warn_from_inodes[cnt].w_type = QUOTA_NL_NOWARN;
1925 warn_from_space[cnt].w_type = QUOTA_NL_NOWARN;
1926 }
b9ba6f94
NY		 1927
1928 spin_lock(&dq_data_lock);
cc33412f 1929 if (IS_NOQUOTA(inode)) { /* File without quota accounting? */
b9ba6f94 1930 spin_unlock(&dq_data_lock);
bc8e5f07 1931 return 0;
cc33412f 1932 }
740d9dcd 1933 cur_space = inode_get_bytes(inode);
fd8fbfc1 1934 rsv_space = inode_get_rsv_space(inode);
740d9dcd 1935 space = cur_space + rsv_space;
1da177e4
LT		 1936 /* Build the transfer_from list and check the limits */
1937 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
9e32784b
D		 1938 /*
1939 * Skip changes for same uid or gid or for turned off quota-type.
1940 */
dd6f3c6d 1941 if (!transfer_to[cnt])
1da177e4 1942 continue;
9e32784b
D		 1943 /* Avoid races with quotaoff() */
1944 if (!sb_has_quota_active(inode->i_sb, cnt))
1945 continue;
1946 is_valid[cnt] = 1;
2d0fa467 1947 transfer_from[cnt] = i_dquot(inode)[cnt];
7a9ca53a 1948 ret = check_idq(transfer_to[cnt], inode_usage, &warn_to[cnt]);
efd8f0e6
CH		 1949 if (ret)
1950 goto over_quota;
bf097aaf 1951 ret = check_bdq(transfer_to[cnt], space, 0, &warn_to[cnt]);
efd8f0e6 1952 if (ret)
cc33412f 1953 goto over_quota;
1da177e4
LT		 1954 }
1955
1956 /*
1957 * Finally perform the needed transfer from transfer_from to transfer_to
1958 */
1959 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
9e32784b 1960 if (!is_valid[cnt])
1da177e4 1961 continue;
1da177e4
LT		 1962 /* Due to IO error we might not have transfer_from[] structure */
1963 if (transfer_from[cnt]) {
bf097aaf 1964 int wtype;
7a9ca53a 1965 wtype = info_idq_free(transfer_from[cnt], inode_usage);
bf097aaf
JK		 1966 if (wtype != QUOTA_NL_NOWARN)
1967 prepare_warning(&warn_from_inodes[cnt],
1968 transfer_from[cnt], wtype);
1969 wtype = info_bdq_free(transfer_from[cnt], space);
1970 if (wtype != QUOTA_NL_NOWARN)
1971 prepare_warning(&warn_from_space[cnt],
1972 transfer_from[cnt], wtype);
7a9ca53a 1973 dquot_decr_inodes(transfer_from[cnt], inode_usage);
740d9dcd
MC		 1974 dquot_decr_space(transfer_from[cnt], cur_space);
1975 dquot_free_reserved_space(transfer_from[cnt],
1976 rsv_space);
1da177e4
LT		 1977 }
1978
7a9ca53a 1979 dquot_incr_inodes(transfer_to[cnt], inode_usage);
740d9dcd
MC		 1980 dquot_incr_space(transfer_to[cnt], cur_space);
1981 dquot_resv_space(transfer_to[cnt], rsv_space);
1da177e4 1982
2d0fa467 1983 i_dquot(inode)[cnt] = transfer_to[cnt];
1da177e4 1984 }
1da177e4 1985 spin_unlock(&dq_data_lock);
cc33412f 1986
dc52dd3a
DM		 1987 mark_all_dquot_dirty(transfer_from);
1988 mark_all_dquot_dirty(transfer_to);
bf097aaf
JK		 1989 flush_warnings(warn_to);
1990 flush_warnings(warn_from_inodes);
1991 flush_warnings(warn_from_space);
bc8e5f07 1992 /* Pass back references to put */
dc52dd3a 1993 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
9e32784b
D		 1994 if (is_valid[cnt])
1995 transfer_to[cnt] = transfer_from[cnt];
86f3cbec 1996 return 0;
cc33412f
JK		 1997over_quota:
1998 spin_unlock(&dq_data_lock);
bf097aaf 1999 flush_warnings(warn_to);
86f3cbec 2000 return ret;
1da177e4 2001}
bc8e5f07 2002EXPORT_SYMBOL(__dquot_transfer);
1da177e4 2003
8ddd69d6
DM		 2004/* Wrapper for transferring ownership of an inode for uid/gid only
2005 * Called from FSXXX_setattr()
2006 */
b43fa828 2007int dquot_transfer(struct inode *inode, struct iattr *iattr)
b85f4b87 2008{
bc8e5f07 2009 struct dquot *transfer_to[MAXQUOTAS] = {};
6184fc0b 2010 struct dquot *dquot;
bc8e5f07
JK		 2011 struct super_block *sb = inode->i_sb;
2012 int ret;
8ddd69d6 2013
189eef59 2014 if (!dquot_active(inode))
bc8e5f07 2015 return 0;
12755627 2016
6184fc0b
JK		 2017 if (iattr->ia_valid & ATTR_UID && !uid_eq(iattr->ia_uid, inode->i_uid)){
2018 dquot = dqget(sb, make_kqid_uid(iattr->ia_uid));
2019 if (IS_ERR(dquot)) {
2020 if (PTR_ERR(dquot) != -ESRCH) {
2021 ret = PTR_ERR(dquot);
2022 goto out_put;
2023 }
2024 dquot = NULL;
2025 }
2026 transfer_to[USRQUOTA] = dquot;
2027 }
2028 if (iattr->ia_valid & ATTR_GID && !gid_eq(iattr->ia_gid, inode->i_gid)){
2029 dquot = dqget(sb, make_kqid_gid(iattr->ia_gid));
2030 if (IS_ERR(dquot)) {
2031 if (PTR_ERR(dquot) != -ESRCH) {
2032 ret = PTR_ERR(dquot);
2033 goto out_put;
2034 }
2035 dquot = NULL;
2036 }
2037 transfer_to[GRPQUOTA] = dquot;
2038 }
bc8e5f07 2039 ret = __dquot_transfer(inode, transfer_to);
6184fc0b 2040out_put:
bc8e5f07
JK		 2041 dqput_all(transfer_to);
2042 return ret;
b85f4b87 2043}
b43fa828 2044EXPORT_SYMBOL(dquot_transfer);
b85f4b87 2045
1da177e4
LT		 2046/*
2047 * Write info of quota file to disk
2048 */
2049int dquot_commit_info(struct super_block *sb, int type)
2050{
1da177e4
LT		 2051 struct quota_info *dqopt = sb_dqopt(sb);
2052
9a8ae30e 2053 return dqopt->ops[type]->write_file_info(sb, type);
1da177e4 2054}
08d0350c 2055EXPORT_SYMBOL(dquot_commit_info);
1da177e4 2056
be6257b2
JK		 2057int dquot_get_next_id(struct super_block *sb, struct kqid *qid)
2058{
2059 struct quota_info *dqopt = sb_dqopt(sb);
be6257b2 2060
9d1ccbe7
JK		 2061 if (!sb_has_quota_active(sb, qid->type))
2062 return -ESRCH;
2063 if (!dqopt->ops[qid->type]->get_next_id)
2064 return -ENOSYS;
f14618c6 2065 return dqopt->ops[qid->type]->get_next_id(sb, qid);
be6257b2
JK		 2066}
2067EXPORT_SYMBOL(dquot_get_next_id);
2068
1da177e4
LT		 2069/*
2070 * Definitions of diskquota operations.
2071 */
61e225dc 2072const struct dquot_operations dquot_operations = {
1da177e4
LT		 2073 .write_dquot = dquot_commit,
2074 .acquire_dquot = dquot_acquire,
2075 .release_dquot = dquot_release,
2076 .mark_dirty = dquot_mark_dquot_dirty,
74f783af
JK		 2077 .write_info = dquot_commit_info,
2078 .alloc_dquot = dquot_alloc,
2079 .destroy_dquot = dquot_destroy,
be6257b2 2080 .get_next_id = dquot_get_next_id,
1da177e4 2081};
123e9caf 2082EXPORT_SYMBOL(dquot_operations);
1da177e4 2083
907f4554
CH		 2084/*
2085 * Generic helper for ->open on filesystems supporting disk quotas.
2086 */
2087int dquot_file_open(struct inode *inode, struct file *file)
2088{
2089 int error;
2090
2091 error = generic_file_open(inode, file);
2092 if (!error && (file->f_mode & FMODE_WRITE))
871a2931 2093 dquot_initialize(inode);
907f4554
CH		 2094 return error;
2095}
2096EXPORT_SYMBOL(dquot_file_open);
2097
1da177e4
LT		 2098/*
2099 * Turn quota off on a device. type == -1 ==> quotaoff for all types (umount)
2100 */
0f0dd62f 2101int dquot_disable(struct super_block *sb, int type, unsigned int flags)
1da177e4 2102{
0ff5af83 2103 int cnt, ret = 0;
1da177e4
LT		 2104 struct quota_info *dqopt = sb_dqopt(sb);
2105 struct inode *toputinode[MAXQUOTAS];
1da177e4 2106
7d6cd73d
JK		 2107 /* s_umount should be held in exclusive mode */
2108 if (WARN_ON_ONCE(down_read_trylock(&sb->s_umount)))
2109 up_read(&sb->s_umount);
2110
f55abc0f
JK		 2111 /* Cannot turn off usage accounting without turning off limits, or
2112 * suspend quotas and simultaneously turn quotas off. */
2113 if ((flags & DQUOT_USAGE_ENABLED && !(flags & DQUOT_LIMITS_ENABLED))
2114 || (flags & DQUOT_SUSPENDED && flags & (DQUOT_LIMITS_ENABLED |
2115 DQUOT_USAGE_ENABLED)))
2116 return -EINVAL;
2117
9377abd0
JK		 2118 /*
2119 * Skip everything if there's nothing to do. We have to do this because
2120 * sometimes we are called when fill_super() failed and calling
2121 * sync_fs() in such cases does no good.
2122 */
c3b00446 2123 if (!sb_any_quota_loaded(sb))
9377abd0 2124 return 0;
c3b00446 2125
1da177e4
LT		 2126 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
2127 toputinode[cnt] = NULL;
1da177e4
LT		 2128 if (type != -1 && cnt != type)
2129 continue;
f55abc0f 2130 if (!sb_has_quota_loaded(sb, cnt))
0ff5af83 2131 continue;
f55abc0f
JK		 2132
2133 if (flags & DQUOT_SUSPENDED) {
cc33412f 2134 spin_lock(&dq_state_lock);
f55abc0f
JK		 2135 dqopt->flags |=
2136 dquot_state_flag(DQUOT_SUSPENDED, cnt);
cc33412f 2137 spin_unlock(&dq_state_lock);
f55abc0f 2138 } else {
cc33412f 2139 spin_lock(&dq_state_lock);
f55abc0f
JK		 2140 dqopt->flags &= ~dquot_state_flag(flags, cnt);
2141 /* Turning off suspended quotas? */
2142 if (!sb_has_quota_loaded(sb, cnt) &&
2143 sb_has_quota_suspended(sb, cnt)) {
2144 dqopt->flags &= ~dquot_state_flag(
2145 DQUOT_SUSPENDED, cnt);
cc33412f 2146 spin_unlock(&dq_state_lock);
f55abc0f
JK		 2147 iput(dqopt->files[cnt]);
2148 dqopt->files[cnt] = NULL;
2149 continue;
2150 }
cc33412f 2151 spin_unlock(&dq_state_lock);
0ff5af83 2152 }
f55abc0f
JK		 2153
2154 /* We still have to keep quota loaded? */
2155 if (sb_has_quota_loaded(sb, cnt) && !(flags & DQUOT_SUSPENDED))
1da177e4 2156 continue;
1da177e4
LT		 2157
2158 /* Note: these are blocking operations */
2159 drop_dquot_ref(sb, cnt);
2160 invalidate_dquots(sb, cnt);
2161 /*
268157ba
JK		 2162 * Now all dquots should be invalidated, all writes done so we
2163 * should be only users of the info. No locks needed.
1da177e4
LT		 2164 */
2165 if (info_dirty(&dqopt->info[cnt]))
2166 sb->dq_op->write_info(sb, cnt);
2167 if (dqopt->ops[cnt]->free_file_info)
2168 dqopt->ops[cnt]->free_file_info(sb, cnt);
2169 put_quota_format(dqopt->info[cnt].dqi_format);
2170
2171 toputinode[cnt] = dqopt->files[cnt];
f55abc0f 2172 if (!sb_has_quota_loaded(sb, cnt))
0ff5af83 2173 dqopt->files[cnt] = NULL;
1da177e4
LT		 2174 dqopt->info[cnt].dqi_flags = 0;
2175 dqopt->info[cnt].dqi_igrace = 0;
2176 dqopt->info[cnt].dqi_bgrace = 0;
2177 dqopt->ops[cnt] = NULL;
2178 }
ca785ec6
JK		 2179
2180 /* Skip syncing and setting flags if quota files are hidden */
2181 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE)
2182 goto put_inodes;
2183
1da177e4 2184 /* Sync the superblock so that buffers with quota data are written to
7b7b1ace 2185 * disk (and so userspace sees correct data afterwards). */
1da177e4
LT		 2186 if (sb->s_op->sync_fs)
2187 sb->s_op->sync_fs(sb, 1);
2188 sync_blockdev(sb->s_bdev);
2189 /* Now the quota files are just ordinary files and we can set the
2190 * inode flags back. Moreover we discard the pagecache so that
2191 * userspace sees the writes we did bypassing the pagecache. We
2192 * must also discard the blockdev buffers so that we see the
2193 * changes done by userspace on the next quotaon() */
2194 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
2700e606
JK		 2195 /* This can happen when suspending quotas on remount-ro... */
2196 if (toputinode[cnt] && !sb_has_quota_loaded(sb, cnt)) {
c3b00446 2197 inode_lock(toputinode[cnt]);
aad6cde9 2198 toputinode[cnt]->i_flags &= ~S_NOQUOTA;
c3b00446
JK		 2199 truncate_inode_pages(&toputinode[cnt]->i_data, 0);
2200 inode_unlock(toputinode[cnt]);
2201 mark_inode_dirty_sync(toputinode[cnt]);
ca785ec6
JK		 2202 }
2203 if (sb->s_bdev)
2204 invalidate_bdev(sb->s_bdev);
2205put_inodes:
2206 for (cnt = 0; cnt < MAXQUOTAS; cnt++)
2207 if (toputinode[cnt]) {
0ff5af83 2208 /* On remount RO, we keep the inode pointer so that we
f55abc0f
JK		 2209 * can reenable quota on the subsequent remount RW. We
2210 * have to check 'flags' variable and not use sb_has_
2211 * function because another quotaon / quotaoff could
2212 * change global state before we got here. We refuse
2213 * to suspend quotas when there is pending delete on
2214 * the quota file... */
2215 if (!(flags & DQUOT_SUSPENDED))
0ff5af83
JK		 2216 iput(toputinode[cnt]);
2217 else if (!toputinode[cnt]->i_nlink)
2218 ret = -EBUSY;
1da177e4 2219 }
0ff5af83 2220 return ret;
1da177e4 2221}
0f0dd62f 2222EXPORT_SYMBOL(dquot_disable);
1da177e4 2223
287a8095 2224int dquot_quota_off(struct super_block *sb, int type)
f55abc0f 2225{
0f0dd62f
CH		 2226 return dquot_disable(sb, type,
2227 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
f55abc0f 2228}
287a8095 2229EXPORT_SYMBOL(dquot_quota_off);
0f0dd62f 2230
1da177e4
LT		 2231/*
2232 * Turn quotas on on a device
2233 */
2234
f55abc0f
JK		 2235/*
2236 * Helper function to turn quotas on when we already have the inode of
2237 * quota file and no quota information is loaded.
2238 */
2239static int vfs_load_quota_inode(struct inode *inode, int type, int format_id,
2240 unsigned int flags)
1da177e4
LT		 2241{
2242 struct quota_format_type *fmt = find_quota_format(format_id);
2243 struct super_block *sb = inode->i_sb;
2244 struct quota_info *dqopt = sb_dqopt(sb);
2245 int error;
1da177e4
LT		 2246
2247 if (!fmt)
2248 return -ESRCH;
2249 if (!S_ISREG(inode->i_mode)) {
2250 error = -EACCES;
2251 goto out_fmt;
2252 }
2253 if (IS_RDONLY(inode)) {
2254 error = -EROFS;
2255 goto out_fmt;
2256 }
847aac64
LX		 2257 if (!sb->s_op->quota_write || !sb->s_op->quota_read ||
2258 (type == PRJQUOTA && sb->dq_op->get_projid == NULL)) {
1da177e4
LT		 2259 error = -EINVAL;
2260 goto out_fmt;
2261 }
5c004828
EB		 2262 /* Filesystems outside of init_user_ns not yet supported */
2263 if (sb->s_user_ns != &init_user_ns) {
2264 error = -EINVAL;
2265 goto out_fmt;
2266 }
f55abc0f
JK		 2267 /* Usage always has to be set... */
2268 if (!(flags & DQUOT_USAGE_ENABLED)) {
2269 error = -EINVAL;
2270 goto out_fmt;
2271 }
c3b00446
JK		 2272 if (sb_has_quota_loaded(sb, type)) {
2273 error = -EBUSY;
2274 goto out_fmt;
2275 }
1da177e4 2276
ca785ec6 2277 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) {
ab94c39b
JK		 2278 /* As we bypass the pagecache we must now flush all the
2279 * dirty data and invalidate caches so that kernel sees
2280 * changes from userspace. It is not enough to just flush
2281 * the quota file since if blocksize < pagesize, invalidation
2282 * of the cache could fail because of other unrelated dirty
2283 * data */
2284 sync_filesystem(sb);
ca785ec6
JK		 2285 invalidate_bdev(sb->s_bdev);
2286 }
ca785ec6
JK		 2287
2288 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE)) {
2289 /* We don't want quota and atime on quota files (deadlocks
2290 * possible) Also nobody should write to the file - we use
2291 * special IO operations which ignore the immutable bit. */
5955102c 2292 inode_lock(inode);
aad6cde9 2293 inode->i_flags |= S_NOQUOTA;
5955102c 2294 inode_unlock(inode);
26245c94
JK		 2295 /*
2296 * When S_NOQUOTA is set, remove dquot references as no more
2297 * references can be added
2298 */
9f754758 2299 __dquot_drop(inode);
ca785ec6 2300 }
1da177e4
LT		 2301
2302 error = -EIO;
2303 dqopt->files[type] = igrab(inode);
2304 if (!dqopt->files[type])
c3b00446 2305 goto out_file_flags;
1da177e4
LT		 2306 error = -EINVAL;
2307 if (!fmt->qf_ops->check_quota_file(sb, type))
2308 goto out_file_init;
2309
2310 dqopt->ops[type] = fmt->qf_ops;
2311 dqopt->info[type].dqi_format = fmt;
0ff5af83 2312 dqopt->info[type].dqi_fmt_id = format_id;
1da177e4 2313 INIT_LIST_HEAD(&dqopt->info[type].dqi_dirty_list);
268157ba 2314 error = dqopt->ops[type]->read_file_info(sb, type);
42fdb858 2315 if (error < 0)
1da177e4 2316 goto out_file_init;
15512377
JK		 2317 if (dqopt->flags & DQUOT_QUOTA_SYS_FILE) {
2318 spin_lock(&dq_data_lock);
46fe44ce 2319 dqopt->info[type].dqi_flags |= DQF_SYS_FILE;
15512377
JK		 2320 spin_unlock(&dq_data_lock);
2321 }
cc33412f 2322 spin_lock(&dq_state_lock);
f55abc0f 2323 dqopt->flags |= dquot_state_flag(flags, type);
cc33412f 2324 spin_unlock(&dq_state_lock);
1da177e4
LT		 2325
2326 add_dquot_ref(sb, type);
1da177e4
LT		 2327
2328 return 0;
2329
2330out_file_init:
2331 dqopt->files[type] = NULL;
2332 iput(inode);
c3b00446 2333out_file_flags:
aad6cde9
JK		 2334 inode_lock(inode);
2335 inode->i_flags &= ~S_NOQUOTA;
2336 inode_unlock(inode);
1da177e4
LT		 2337out_fmt:
2338 put_quota_format(fmt);
2339
2340 return error;
2341}
2342
0ff5af83 2343/* Reenable quotas on remount RW */
0f0dd62f 2344int dquot_resume(struct super_block *sb, int type)
0ff5af83
JK		 2345{
2346 struct quota_info *dqopt = sb_dqopt(sb);
2347 struct inode *inode;
0f0dd62f 2348 int ret = 0, cnt;
f55abc0f 2349 unsigned int flags;
0ff5af83 2350
7d6cd73d
JK		 2351 /* s_umount should be held in exclusive mode */
2352 if (WARN_ON_ONCE(down_read_trylock(&sb->s_umount)))
2353 up_read(&sb->s_umount);
2354
0f0dd62f
CH		 2355 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
2356 if (type != -1 && cnt != type)
2357 continue;
c3b00446 2358 if (!sb_has_quota_suspended(sb, cnt))
0f0dd62f 2359 continue;
c3b00446 2360
0f0dd62f
CH		 2361 inode = dqopt->files[cnt];
2362 dqopt->files[cnt] = NULL;
2363 spin_lock(&dq_state_lock);
2364 flags = dqopt->flags & dquot_state_flag(DQUOT_USAGE_ENABLED |
2365 DQUOT_LIMITS_ENABLED,
2366 cnt);
2367 dqopt->flags &= ~dquot_state_flag(DQUOT_STATE_FLAGS, cnt);
2368 spin_unlock(&dq_state_lock);
0ff5af83 2369
0f0dd62f
CH		 2370 flags = dquot_generic_flag(flags, cnt);
2371 ret = vfs_load_quota_inode(inode, cnt,
2372 dqopt->info[cnt].dqi_fmt_id, flags);
2373 iput(inode);
2374 }
0ff5af83
JK		 2375
2376 return ret;
2377}
0f0dd62f 2378EXPORT_SYMBOL(dquot_resume);
0ff5af83 2379
f00c9e44 2380int dquot_quota_on(struct super_block *sb, int type, int format_id,
8c54ca9c 2381 const struct path *path)
77e69dac
AV		 2382{
2383 int error = security_quota_on(path->dentry);
2384 if (error)
2385 return error;
2386 /* Quota file not on the same filesystem? */
d8c9584e 2387 if (path->dentry->d_sb != sb)
77e69dac
AV		 2388 error = -EXDEV;
2389 else
dea655c2 2390 error = vfs_load_quota_inode(d_inode(path->dentry), type,
f55abc0f
JK		 2391 format_id, DQUOT_USAGE_ENABLED |
2392 DQUOT_LIMITS_ENABLED);
77e69dac
AV		 2393 return error;
2394}
287a8095 2395EXPORT_SYMBOL(dquot_quota_on);
1da177e4 2396
f55abc0f
JK		 2397/*
2398 * More powerful function for turning on quotas allowing setting
2399 * of individual quota flags
2400 */
287a8095
CH		 2401int dquot_enable(struct inode *inode, int type, int format_id,
2402 unsigned int flags)
f55abc0f 2403{
f55abc0f 2404 struct super_block *sb = inode->i_sb;
f55abc0f
JK		 2405
2406 /* Just unsuspend quotas? */
0f0dd62f 2407 BUG_ON(flags & DQUOT_SUSPENDED);
7d6cd73d
JK		 2408 /* s_umount should be held in exclusive mode */
2409 if (WARN_ON_ONCE(down_read_trylock(&sb->s_umount)))
2410 up_read(&sb->s_umount);
0f0dd62f 2411
f55abc0f
JK		 2412 if (!flags)
2413 return 0;
2414 /* Just updating flags needed? */
2415 if (sb_has_quota_loaded(sb, type)) {
f55abc0f 2416 if (flags & DQUOT_USAGE_ENABLED &&
c3b00446
JK		 2417 sb_has_quota_usage_enabled(sb, type))
2418 return -EBUSY;
f55abc0f 2419 if (flags & DQUOT_LIMITS_ENABLED &&
c3b00446
JK		 2420 sb_has_quota_limits_enabled(sb, type))
2421 return -EBUSY;
cc33412f 2422 spin_lock(&dq_state_lock);
f55abc0f 2423 sb_dqopt(sb)->flags |= dquot_state_flag(flags, type);
cc33412f 2424 spin_unlock(&dq_state_lock);
c3b00446 2425 return 0;
f55abc0f
JK		 2426 }
2427
f55abc0f
JK		 2428 return vfs_load_quota_inode(inode, type, format_id, flags);
2429}
287a8095 2430EXPORT_SYMBOL(dquot_enable);
f55abc0f 2431
1da177e4
LT		 2432/*
2433 * This function is used when filesystem needs to initialize quotas
2434 * during mount time.
2435 */
287a8095 2436int dquot_quota_on_mount(struct super_block *sb, char *qf_name,
84de856e 2437 int format_id, int type)
1da177e4 2438{
84de856e 2439 struct dentry *dentry;
1da177e4
LT		 2440 int error;
2441
e12a4e8a 2442 dentry = lookup_one_len_unlocked(qf_name, sb->s_root, strlen(qf_name));
84de856e
CH		 2443 if (IS_ERR(dentry))
2444 return PTR_ERR(dentry);
2445
dea655c2 2446 if (d_really_is_negative(dentry)) {
154f484b
JK		 2447 error = -ENOENT;
2448 goto out;
2449 }
2450
1da177e4 2451 error = security_quota_on(dentry);
84de856e 2452 if (!error)
dea655c2 2453 error = vfs_load_quota_inode(d_inode(dentry), type, format_id,
f55abc0f 2454 DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
84de856e 2455
154f484b 2456out:
84de856e
CH		 2457 dput(dentry);
2458 return error;
1da177e4 2459}
287a8095 2460EXPORT_SYMBOL(dquot_quota_on_mount);
b85f4b87 2461
3e2af67e
JK		 2462static int dquot_quota_enable(struct super_block *sb, unsigned int flags)
2463{
2464 int ret;
2465 int type;
2466 struct quota_info *dqopt = sb_dqopt(sb);
2467
2468 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE))
2469 return -ENOSYS;
2470 /* Accounting cannot be turned on while fs is mounted */
2471 flags &= ~(FS_QUOTA_UDQ_ACCT | FS_QUOTA_GDQ_ACCT | FS_QUOTA_PDQ_ACCT);
2472 if (!flags)
2473 return -EINVAL;
2474 for (type = 0; type < MAXQUOTAS; type++) {
2475 if (!(flags & qtype_enforce_flag(type)))
2476 continue;
2477 /* Can't enforce without accounting */
2478 if (!sb_has_quota_usage_enabled(sb, type))
2479 return -EINVAL;
2480 ret = dquot_enable(dqopt->files[type], type,
2481 dqopt->info[type].dqi_fmt_id,
2482 DQUOT_LIMITS_ENABLED);
2483 if (ret < 0)
2484 goto out_err;
2485 }
2486 return 0;
2487out_err:
2488 /* Backout enforcement enablement we already did */
2489 for (type--; type >= 0; type--) {
2490 if (flags & qtype_enforce_flag(type))
2491 dquot_disable(sb, type, DQUOT_LIMITS_ENABLED);
2492 }
2493 /* Error code translation for better compatibility with XFS */
2494 if (ret == -EBUSY)
2495 ret = -EEXIST;
2496 return ret;
2497}
2498
2499static int dquot_quota_disable(struct super_block *sb, unsigned int flags)
2500{
2501 int ret;
2502 int type;
2503 struct quota_info *dqopt = sb_dqopt(sb);
2504
2505 if (!(dqopt->flags & DQUOT_QUOTA_SYS_FILE))
2506 return -ENOSYS;
2507 /*
2508 * We don't support turning off accounting via quotactl. In principle
2509 * quota infrastructure can do this but filesystems don't expect
2510 * userspace to be able to do it.
2511 */
2512 if (flags &
2513 (FS_QUOTA_UDQ_ACCT | FS_QUOTA_GDQ_ACCT | FS_QUOTA_PDQ_ACCT))
2514 return -EOPNOTSUPP;
2515
2516 /* Filter out limits not enabled */
2517 for (type = 0; type < MAXQUOTAS; type++)
2518 if (!sb_has_quota_limits_enabled(sb, type))
2519 flags &= ~qtype_enforce_flag(type);
2520 /* Nothing left? */
2521 if (!flags)
2522 return -EEXIST;
2523 for (type = 0; type < MAXQUOTAS; type++) {
2524 if (flags & qtype_enforce_flag(type)) {
2525 ret = dquot_disable(sb, type, DQUOT_LIMITS_ENABLED);
2526 if (ret < 0)
2527 goto out_err;
2528 }
2529 }
2530 return 0;
2531out_err:
2532 /* Backout enforcement disabling we already did */
2533 for (type--; type >= 0; type--) {
2534 if (flags & qtype_enforce_flag(type))
2535 dquot_enable(dqopt->files[type], type,
2536 dqopt->info[type].dqi_fmt_id,
2537 DQUOT_LIMITS_ENABLED);
2538 }
2539 return ret;
2540}
2541
1da177e4 2542/* Generic routine for getting common part of quota structure */
14bf61ff 2543static void do_get_dqblk(struct dquot *dquot, struct qc_dqblk *di)
1da177e4
LT		 2544{
2545 struct mem_dqblk *dm = &dquot->dq_dqb;
2546
b9b2dd36 2547 memset(di, 0, sizeof(*di));
1da177e4 2548 spin_lock(&dq_data_lock);
14bf61ff
JK		 2549 di->d_spc_hardlimit = dm->dqb_bhardlimit;
2550 di->d_spc_softlimit = dm->dqb_bsoftlimit;
b9b2dd36
CH		 2551 di->d_ino_hardlimit = dm->dqb_ihardlimit;
2552 di->d_ino_softlimit = dm->dqb_isoftlimit;
14bf61ff
JK		 2553 di->d_space = dm->dqb_curspace + dm->dqb_rsvspace;
2554 di->d_ino_count = dm->dqb_curinodes;
2555 di->d_spc_timer = dm->dqb_btime;
2556 di->d_ino_timer = dm->dqb_itime;
1da177e4
LT		 2557 spin_unlock(&dq_data_lock);
2558}
2559
74a8a103 2560int dquot_get_dqblk(struct super_block *sb, struct kqid qid,
14bf61ff 2561 struct qc_dqblk *di)
1da177e4
LT		 2562{
2563 struct dquot *dquot;
2564
aca645a6 2565 dquot = dqget(sb, qid);
6184fc0b
JK		 2566 if (IS_ERR(dquot))
2567 return PTR_ERR(dquot);
1da177e4
LT		 2568 do_get_dqblk(dquot, di);
2569 dqput(dquot);
cc33412f 2570
1da177e4
LT		 2571 return 0;
2572}
287a8095 2573EXPORT_SYMBOL(dquot_get_dqblk);
1da177e4 2574
be6257b2
JK		 2575int dquot_get_next_dqblk(struct super_block *sb, struct kqid *qid,
2576 struct qc_dqblk *di)
2577{
2578 struct dquot *dquot;
2579 int err;
2580
2581 if (!sb->dq_op->get_next_id)
2582 return -ENOSYS;
2583 err = sb->dq_op->get_next_id(sb, qid);
2584 if (err < 0)
2585 return err;
2586 dquot = dqget(sb, *qid);
2587 if (IS_ERR(dquot))
2588 return PTR_ERR(dquot);
2589 do_get_dqblk(dquot, di);
2590 dqput(dquot);
2591
2592 return 0;
2593}
2594EXPORT_SYMBOL(dquot_get_next_dqblk);
2595
14bf61ff
JK		 2596#define VFS_QC_MASK \
2597 (QC_SPACE | QC_SPC_SOFT | QC_SPC_HARD | \
2598 QC_INO_COUNT | QC_INO_SOFT | QC_INO_HARD | \
2599 QC_SPC_TIMER | QC_INO_TIMER)
c472b432 2600
1da177e4 2601/* Generic routine for setting common part of quota structure */
14bf61ff 2602static int do_set_dqblk(struct dquot *dquot, struct qc_dqblk *di)
1da177e4
LT		 2603{
2604 struct mem_dqblk *dm = &dquot->dq_dqb;
2605 int check_blim = 0, check_ilim = 0;
4c376dca 2606 struct mem_dqinfo *dqi = &sb_dqopt(dquot->dq_sb)->info[dquot->dq_id.type];
338bf9af 2607
14bf61ff 2608 if (di->d_fieldmask & ~VFS_QC_MASK)
c472b432
CH		 2609 return -EINVAL;
2610
14bf61ff 2611 if (((di->d_fieldmask & QC_SPC_SOFT) &&
b10a0819 2612 di->d_spc_softlimit > dqi->dqi_max_spc_limit) ||
14bf61ff 2613 ((di->d_fieldmask & QC_SPC_HARD) &&
b10a0819 2614 di->d_spc_hardlimit > dqi->dqi_max_spc_limit) ||
14bf61ff 2615 ((di->d_fieldmask & QC_INO_SOFT) &&
b10a0819 2616 (di->d_ino_softlimit > dqi->dqi_max_ino_limit)) ||
14bf61ff 2617 ((di->d_fieldmask & QC_INO_HARD) &&
b10a0819 2618 (di->d_ino_hardlimit > dqi->dqi_max_ino_limit)))
338bf9af 2619 return -ERANGE;
1da177e4
LT		 2620
2621 spin_lock(&dq_data_lock);
14bf61ff
JK		 2622 if (di->d_fieldmask & QC_SPACE) {
2623 dm->dqb_curspace = di->d_space - dm->dqb_rsvspace;
1da177e4 2624 check_blim = 1;
08261673 2625 set_bit(DQ_LASTSET_B + QIF_SPACE_B, &dquot->dq_flags);
1da177e4 2626 }
c472b432 2627
14bf61ff
JK		 2628 if (di->d_fieldmask & QC_SPC_SOFT)
2629 dm->dqb_bsoftlimit = di->d_spc_softlimit;
2630 if (di->d_fieldmask & QC_SPC_HARD)
2631 dm->dqb_bhardlimit = di->d_spc_hardlimit;
2632 if (di->d_fieldmask & (QC_SPC_SOFT | QC_SPC_HARD)) {
1da177e4 2633 check_blim = 1;
08261673 2634 set_bit(DQ_LASTSET_B + QIF_BLIMITS_B, &dquot->dq_flags);
1da177e4 2635 }
c472b432 2636
14bf61ff
JK		 2637 if (di->d_fieldmask & QC_INO_COUNT) {
2638 dm->dqb_curinodes = di->d_ino_count;
1da177e4 2639 check_ilim = 1;
08261673 2640 set_bit(DQ_LASTSET_B + QIF_INODES_B, &dquot->dq_flags);
1da177e4 2641 }
c472b432 2642
14bf61ff 2643 if (di->d_fieldmask & QC_INO_SOFT)
c472b432 2644 dm->dqb_isoftlimit = di->d_ino_softlimit;
14bf61ff 2645 if (di->d_fieldmask & QC_INO_HARD)
c472b432 2646 dm->dqb_ihardlimit = di->d_ino_hardlimit;
14bf61ff 2647 if (di->d_fieldmask & (QC_INO_SOFT | QC_INO_HARD)) {
1da177e4 2648 check_ilim = 1;
08261673 2649 set_bit(DQ_LASTSET_B + QIF_ILIMITS_B, &dquot->dq_flags);
1da177e4 2650 }
c472b432 2651
14bf61ff
JK		 2652 if (di->d_fieldmask & QC_SPC_TIMER) {
2653 dm->dqb_btime = di->d_spc_timer;
e04a88a9 2654 check_blim = 1;
08261673 2655 set_bit(DQ_LASTSET_B + QIF_BTIME_B, &dquot->dq_flags);
4d59bce4 2656 }
c472b432 2657
14bf61ff
JK		 2658 if (di->d_fieldmask & QC_INO_TIMER) {
2659 dm->dqb_itime = di->d_ino_timer;
e04a88a9 2660 check_ilim = 1;
08261673 2661 set_bit(DQ_LASTSET_B + QIF_ITIME_B, &dquot->dq_flags);
4d59bce4 2662 }
1da177e4
LT		 2663
2664 if (check_blim) {
268157ba
JK		 2665 if (!dm->dqb_bsoftlimit ||
2666 dm->dqb_curspace < dm->dqb_bsoftlimit) {
1da177e4
LT		 2667 dm->dqb_btime = 0;
2668 clear_bit(DQ_BLKS_B, &dquot->dq_flags);
14bf61ff 2669 } else if (!(di->d_fieldmask & QC_SPC_TIMER))
268157ba 2670 /* Set grace only if user hasn't provided his own... */
e008bb61 2671 dm->dqb_btime = ktime_get_real_seconds() + dqi->dqi_bgrace;
1da177e4
LT		 2672 }
2673 if (check_ilim) {
268157ba
JK		 2674 if (!dm->dqb_isoftlimit ||
2675 dm->dqb_curinodes < dm->dqb_isoftlimit) {
1da177e4
LT		 2676 dm->dqb_itime = 0;
2677 clear_bit(DQ_INODES_B, &dquot->dq_flags);
14bf61ff 2678 } else if (!(di->d_fieldmask & QC_INO_TIMER))
268157ba 2679 /* Set grace only if user hasn't provided his own... */
e008bb61 2680 dm->dqb_itime = ktime_get_real_seconds() + dqi->dqi_igrace;
1da177e4 2681 }
268157ba
JK		 2682 if (dm->dqb_bhardlimit || dm->dqb_bsoftlimit || dm->dqb_ihardlimit ||
2683 dm->dqb_isoftlimit)
1da177e4
LT		 2684 clear_bit(DQ_FAKE_B, &dquot->dq_flags);
2685 else
2686 set_bit(DQ_FAKE_B, &dquot->dq_flags);
2687 spin_unlock(&dq_data_lock);
2688 mark_dquot_dirty(dquot);
338bf9af
AP		 2689
2690 return 0;
1da177e4
LT		 2691}
2692
74a8a103 2693int dquot_set_dqblk(struct super_block *sb, struct kqid qid,
14bf61ff 2694 struct qc_dqblk *di)
1da177e4
LT		 2695{
2696 struct dquot *dquot;
338bf9af 2697 int rc;
1da177e4 2698
aca645a6 2699 dquot = dqget(sb, qid);
6184fc0b
JK		 2700 if (IS_ERR(dquot)) {
2701 rc = PTR_ERR(dquot);
f55abc0f 2702 goto out;
1da177e4 2703 }
338bf9af 2704 rc = do_set_dqblk(dquot, di);
1da177e4 2705 dqput(dquot);
f55abc0f 2706out:
338bf9af 2707 return rc;
1da177e4 2708}
287a8095 2709EXPORT_SYMBOL(dquot_set_dqblk);
1da177e4
LT		 2710
2711/* Generic routine for getting common part of quota file information */
0a240339 2712int dquot_get_state(struct super_block *sb, struct qc_state *state)
1da177e4
LT		 2713{
2714 struct mem_dqinfo *mi;
0a240339
JK		 2715 struct qc_type_state *tstate;
2716 struct quota_info *dqopt = sb_dqopt(sb);
2717 int type;
1da177e4 2718
0a240339
JK		 2719 memset(state, 0, sizeof(*state));
2720 for (type = 0; type < MAXQUOTAS; type++) {
2721 if (!sb_has_quota_active(sb, type))
2722 continue;
2723 tstate = state->s_state + type;
2724 mi = sb_dqopt(sb)->info + type;
2725 tstate->flags = QCI_ACCT_ENABLED;
2726 spin_lock(&dq_data_lock);
2727 if (mi->dqi_flags & DQF_SYS_FILE)
2728 tstate->flags |= QCI_SYSFILE;
2729 if (mi->dqi_flags & DQF_ROOT_SQUASH)
2730 tstate->flags |= QCI_ROOT_SQUASH;
2731 if (sb_has_quota_limits_enabled(sb, type))
2732 tstate->flags |= QCI_LIMITS_ENFORCED;
2733 tstate->spc_timelimit = mi->dqi_bgrace;
2734 tstate->ino_timelimit = mi->dqi_igrace;
2735 tstate->ino = dqopt->files[type]->i_ino;
2736 tstate->blocks = dqopt->files[type]->i_blocks;
2737 tstate->nextents = 1; /* We don't know... */
2738 spin_unlock(&dq_data_lock);
1da177e4 2739 }
1da177e4
LT		 2740 return 0;
2741}
0a240339 2742EXPORT_SYMBOL(dquot_get_state);
1da177e4
LT		 2743
2744/* Generic routine for setting common part of quota file information */
5eacb2ac 2745int dquot_set_dqinfo(struct super_block *sb, int type, struct qc_info *ii)
1da177e4
LT		 2746{
2747 struct mem_dqinfo *mi;
f55abc0f 2748 int err = 0;
1da177e4 2749
5eacb2ac
JK		 2750 if ((ii->i_fieldmask & QC_WARNS_MASK) ||
2751 (ii->i_fieldmask & QC_RT_SPC_TIMER))
2752 return -EINVAL;
9d1ccbe7
JK		 2753 if (!sb_has_quota_active(sb, type))
2754 return -ESRCH;
1da177e4 2755 mi = sb_dqopt(sb)->info + type;
5eacb2ac
JK		 2756 if (ii->i_fieldmask & QC_FLAGS) {
2757 if ((ii->i_flags & QCI_ROOT_SQUASH &&
9d1ccbe7
JK		 2758 mi->dqi_format->qf_fmt_id != QFMT_VFS_OLD))
2759 return -EINVAL;
ca6cb091 2760 }
1da177e4 2761 spin_lock(&dq_data_lock);
5eacb2ac
JK		 2762 if (ii->i_fieldmask & QC_SPC_TIMER)
2763 mi->dqi_bgrace = ii->i_spc_timelimit;
2764 if (ii->i_fieldmask & QC_INO_TIMER)
2765 mi->dqi_igrace = ii->i_ino_timelimit;
2766 if (ii->i_fieldmask & QC_FLAGS) {
2767 if (ii->i_flags & QCI_ROOT_SQUASH)
2768 mi->dqi_flags |= DQF_ROOT_SQUASH;
2769 else
2770 mi->dqi_flags &= ~DQF_ROOT_SQUASH;
2771 }
1da177e4
LT		 2772 spin_unlock(&dq_data_lock);
2773 mark_info_dirty(sb, type);
2774 /* Force write to disk */
2775 sb->dq_op->write_info(sb, type);
f55abc0f 2776 return err;
1da177e4 2777}
287a8095 2778EXPORT_SYMBOL(dquot_set_dqinfo);
1da177e4 2779
3e2af67e
JK		 2780const struct quotactl_ops dquot_quotactl_sysfile_ops = {
2781 .quota_enable = dquot_quota_enable,
2782 .quota_disable = dquot_quota_disable,
2783 .quota_sync = dquot_quota_sync,
0a240339 2784 .get_state = dquot_get_state,
3e2af67e
JK		 2785 .set_info = dquot_set_dqinfo,
2786 .get_dqblk = dquot_get_dqblk,
be6257b2 2787 .get_nextdqblk = dquot_get_next_dqblk,
3e2af67e
JK		 2788 .set_dqblk = dquot_set_dqblk
2789};
2790EXPORT_SYMBOL(dquot_quotactl_sysfile_ops);
2791
dde95888
DM		 2792static int do_proc_dqstats(struct ctl_table *table, int write,
2793 void __user *buffer, size_t *lenp, loff_t *ppos)
2794{
dde95888 2795 unsigned int type = (int *)table->data - dqstats.stat;
f32764bd
DM		 2796
2797 /* Update global table */
2798 dqstats.stat[type] =
2799 percpu_counter_sum_positive(&dqstats.counter[type]);
dde95888
DM		 2800 return proc_dointvec(table, write, buffer, lenp, ppos);
2801}
2802
e628753b 2803static struct ctl_table fs_dqstats_table[] = {
1da177e4 2804 {
1da177e4 2805 .procname = "lookups",
dde95888 2806 .data = &dqstats.stat[DQST_LOOKUPS],
1da177e4
LT		 2807 .maxlen = sizeof(int),
2808 .mode = 0444,
dde95888 2809 .proc_handler = do_proc_dqstats,
1da177e4
LT		 2810 },
2811 {
1da177e4 2812 .procname = "drops",
dde95888 2813 .data = &dqstats.stat[DQST_DROPS],
1da177e4
LT		 2814 .maxlen = sizeof(int),
2815 .mode = 0444,
dde95888 2816 .proc_handler = do_proc_dqstats,
1da177e4
LT		 2817 },
2818 {
1da177e4 2819 .procname = "reads",
dde95888 2820 .data = &dqstats.stat[DQST_READS],
1da177e4
LT		 2821 .maxlen = sizeof(int),
2822 .mode = 0444,
dde95888 2823 .proc_handler = do_proc_dqstats,
1da177e4
LT		 2824 },
2825 {
1da177e4 2826 .procname = "writes",
dde95888 2827 .data = &dqstats.stat[DQST_WRITES],
1da177e4
LT		 2828 .maxlen = sizeof(int),
2829 .mode = 0444,
dde95888 2830 .proc_handler = do_proc_dqstats,
1da177e4
LT		 2831 },
2832 {
1da177e4 2833 .procname = "cache_hits",
dde95888 2834 .data = &dqstats.stat[DQST_CACHE_HITS],
1da177e4
LT		 2835 .maxlen = sizeof(int),
2836 .mode = 0444,
dde95888 2837 .proc_handler = do_proc_dqstats,
1da177e4
LT		 2838 },
2839 {
1da177e4 2840 .procname = "allocated_dquots",
dde95888 2841 .data = &dqstats.stat[DQST_ALLOC_DQUOTS],
1da177e4
LT		 2842 .maxlen = sizeof(int),
2843 .mode = 0444,
dde95888 2844 .proc_handler = do_proc_dqstats,
1da177e4
LT		 2845 },
2846 {
1da177e4 2847 .procname = "free_dquots",
dde95888 2848 .data = &dqstats.stat[DQST_FREE_DQUOTS],
1da177e4
LT		 2849 .maxlen = sizeof(int),
2850 .mode = 0444,
dde95888 2851 .proc_handler = do_proc_dqstats,
1da177e4
LT		 2852 },
2853 {
1da177e4 2854 .procname = "syncs",
dde95888 2855 .data = &dqstats.stat[DQST_SYNCS],
1da177e4
LT		 2856 .maxlen = sizeof(int),
2857 .mode = 0444,
dde95888 2858 .proc_handler = do_proc_dqstats,
1da177e4 2859 },
8e893469 2860#ifdef CONFIG_PRINT_QUOTA_WARNING
1da177e4 2861 {
1da177e4
LT		 2862 .procname = "warnings",
2863 .data = &flag_print_warnings,
2864 .maxlen = sizeof(int),
2865 .mode = 0644,
6d456111 2866 .proc_handler = proc_dointvec,
1da177e4 2867 },
8e893469 2868#endif
ab09203e 2869 { },
1da177e4
LT		 2870};
2871
e628753b 2872static struct ctl_table fs_table[] = {
1da177e4 2873 {
1da177e4
LT		 2874 .procname = "quota",
2875 .mode = 0555,
2876 .child = fs_dqstats_table,
2877 },
ab09203e 2878 { },
1da177e4
LT		 2879};
2880
e628753b 2881static struct ctl_table sys_table[] = {
1da177e4 2882 {
1da177e4
LT		 2883 .procname = "fs",
2884 .mode = 0555,
2885 .child = fs_table,
2886 },
ab09203e 2887 { },
1da177e4
LT		 2888};
2889
2890static int __init dquot_init(void)
2891{
f32764bd 2892 int i, ret;
1da177e4
LT		 2893 unsigned long nr_hash, order;
2894
2895 printk(KERN_NOTICE "VFS: Disk quotas %s\n", __DQUOT_VERSION__);
2896
0b4d4147 2897 register_sysctl_table(sys_table);
1da177e4 2898
20c2df83 2899 dquot_cachep = kmem_cache_create("dquot",
1da177e4 2900 sizeof(struct dquot), sizeof(unsigned long) * 4,
fffb60f9
PJ		 2901 (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
2902 SLAB_MEM_SPREAD|SLAB_PANIC),
20c2df83 2903 NULL);
1da177e4
LT		 2904
2905 order = 0;
2906 dquot_hash = (struct hlist_head *)__get_free_pages(GFP_ATOMIC, order);
2907 if (!dquot_hash)
2908 panic("Cannot create dquot hash table");
2909
f32764bd 2910 for (i = 0; i < _DQST_DQSTAT_LAST; i++) {
908c7f19 2911 ret = percpu_counter_init(&dqstats.counter[i], 0, GFP_KERNEL);
f32764bd
DM		 2912 if (ret)
2913 panic("Cannot create dquot stat counters");
2914 }
dde95888 2915
1da177e4
LT		 2916 /* Find power-of-two hlist_heads which can fit into allocation */
2917 nr_hash = (1UL << order) * PAGE_SIZE / sizeof(struct hlist_head);
2918 dq_hash_bits = 0;
2919 do {
2920 dq_hash_bits++;
2921 } while (nr_hash >> dq_hash_bits);
2922 dq_hash_bits--;
2923
2924 nr_hash = 1UL << dq_hash_bits;
2925 dq_hash_mask = nr_hash - 1;
2926 for (i = 0; i < nr_hash; i++)
2927 INIT_HLIST_HEAD(dquot_hash + i);
2928
19858e7b
AB		 2929 pr_info("VFS: Dquot-cache hash table entries: %ld (order %ld,"
2930 " %ld bytes)\n", nr_hash, order, (PAGE_SIZE << order));
1da177e4 2931
8e1f936b 2932 register_shrinker(&dqcache_shrinker);
1da177e4
LT		 2933
2934 return 0;
2935}
331221fa 2936fs_initcall(dquot_init);
Linux 6.x block layer and io_uring tree(s)